Fix TensorAlloc copy that was copying the ptr

Realized I can just do alloc.create instead of a all new struct

.gitignore

@@ -1,2 +1,4 @@
 zig-out
 .zig-cache
+mkdocs.yaml
+zig-pkg

README.md

@@ -1,42 +1,55 @@
 # dimal — Dimensional Analysis for Zig
 
-A comptime-first dimensional analysis module for Zig. If you try to add meters to seconds, **it won't compile**. That's the point.
+A dimensional analysis library for Zig with a unified `Tensor` API for scalars, vectors, matrices, and higher-dimensional data. All dimension and unit tracking happens at compile time—zero runtime overhead—and all operations use SIMD intrinsics.
 
-Started by a space simulation where `i128` positions were needed to avoid float imprecision far from the origin, this module grew into a full physical-unit type system with zero runtime overhead.
+If you try to add meters to seconds, it won't compile. That's the point.
 
 > **Source:** [git.bouvais.lu/adrien/zig-dimal](https://git.bouvais.lu/adrien/zig-dimal)  
 > **Minimum Zig version:** `0.16.0`
 
 ---
 
+## Background
+
+Started because I needed `i128` positions for a space simulation to avoid floating-point precision loss far from the origin. Grew into a type system for tracking physical dimensions at compile time. It's been useful enough to share.
+
+- **Compile-time dimension checking** — catch unit mismatches before runtime.
+- **Unified `Tensor` API** — same interface for scalars, vectors, matrices, and higher-rank tensors.
+- **SIMD operations** — vector and matrix code automatically uses SIMD instructions.
+- **Zero runtime cost** — all dimension and scale tracking is erased at compile time.
+- **Supports `i128`** — useful for high-precision fixed-point integer math.
+
+---
+
 ## Features
 
-- **100% comptime** — all dimension and unit tracking happens at compile time. No added memory, *almost* native performance.
-- **Compile-time dimension errors** — adding `Meter` to `Second` is a compile error, not a runtime panic.
+- **Compile-time dimension checking** — all physical-unit tracking happens at compile time.
 - **Automatic unit conversion** — use `.to()` to convert between compatible units (e.g. `km/h` → `m/s`). Scale factors are resolved at comptime.
-* **Full SI prefix & Imperial support** — `pico` through `peta`, plus common Imperial units like `inch`, `ft`, `mi`, `lb`, and `oz`.
-- **Time scale support** — `min`, `hour`, `year` built in.
-- **Scalar and Vector types** — operate on individual values or fixed-size arrays with the same dimensional safety.
-- **Built-in physical quantities** — `dma.Base` provides ready-made types for `Velocity`, `Acceleration`, `Force`, `Energy`, `Pressure`, `ElectricCharge`, `ThermalConductivity`, and many more.
-- **Comparison operations** — `eq`, `ne`, `gt`, `gte`, `lt`, `lte` on both `Scalar` and `Vector`, with automatic scale resolution.
-- **Arithmetic with bare numbers** — multiply or divide a dimensioned value by a `comptime_int`, `comptime_float`, or plain `T` directly. The value is treated as dimensionless; dimensions pass through unchanged.
-- **`abs`, `pow`, `sqrt`** — unary operations with correct dimension tracking (`pow(2)` on `L¹` → `L²`, etc.).
-- **Vector geometry** — `dot` product (returns a `Scalar`), `cross` product (Vec3 only), element-wise `product` (all components multiplied).
-- **Rich formatting** — values print with their unit automatically: `9.81m.s⁻²`, `42m.kg.s⁻¹`, `0.172km`.
-- **`i128` support** — the whole reason this exists. Use large integers for high-precision fixed-point positions without manual conversion.
-- **Tests and benchmarks included** — run them and see how it performs on your machine (results welcome!).
+- **Unified `Tensor` API** — one type for scalars `{1}`, vectors `{N}`, matrices `{M, N}`, and higher-rank tensors.
+- **SIMD operations** — vector and matrix code compiles to SIMD instructions automatically.
+- **Tensor contraction** — `.contract(other, axis_a, axis_b)` for dot products, matrix multiplication, and general tensor contractions.
+- **Full SI prefix support** — `pico` through `peta`, plus Imperial units and time scales.
+- **Physical constants** — Planck, Boltzmann, speed of light, gravitational constant, etc.
+- **Pre-built quantities** — `Velocity`, `Acceleration`, `Force`, `Energy`, `Pressure`, `Charge`, and more.
+- **Basic vector operations** — cross product, length/magnitude, element-wise arithmetic.
+- **Formatting** — values print with units: `9.81m.s⁻²`, `0.172km`.
+
+### Current Limitations
+
+- GPU support not implemented.
+- Performance on small tensors is limited by Zig's vector width.
 
 ---
 
 ## The 7 SI Base Dimensions
 
 | Symbol | Dimension            | SI Unit |
-|--------|----------------------|----------|
+|--------|----------------------|---------|
 | `L`    | Length               | `m`     |
 | `M`    | Mass                 | `g`     |
 | `T`    | Time                 | `s`     |
 | `I`    | Electric Current     | `A`     |
-| `Tp`   | Temperature          | `K`      |
+| `Tr`   | Temperature          | `K`     |
 | `N`    | Amount of Substance  | `mol`   |
 | `J`    | Luminous Intensity   | `cd`    |
 
@@ -44,10 +57,10 @@ Started by a space simulation where `i128` positions were needed to avoid float
 
 ## Installation
 
-### 1. Fetch the dependency
+### 1. Add the dependency (Zig 0.14+)
 
 ```sh
-zig fetch --save git+https://git.bouvais.lu/adrien/zig-dimal#0.1.1
+zig fetch --save git+https://git.bouvais.lu/adrien/zig-dimal#0.2.0
 ```
 
 ### 2. Wire it up in `build.zig`
@@ -57,287 +70,181 @@ const std = @import("std");
 
 pub fn build(b: *std.Build) void {
     const target = b.standardTargetOptions(.{});
-    const dimal = b.dependency("dimal", .{}).module("dimal");
+    const optimize = b.standardOptimizeOption(.{});
+    
+    const dimal = b.dependency("dimal", .{
+        .target = target,
+        .optimize = optimize,
+    }).module("dimal");
 
     const exe = b.addExecutable(.{
-        .name = "my_project",
-        .root_module = b.createModule(.{
+        .name = "my_app",
         .root_source_file = b.path("src/main.zig"),
         .target = target,
-            .imports = &.{.{
-                .name = "dimal",
-                .module = dimal,
-            }},
-        }),
+        .optimize = optimize,
     });
+    exe.root_module.addImport("dimal", dimal);
     b.installArtifact(exe);
 }
 ```
 
-### 3. Import in your code
+### 3. Import and use
 
 ```zig
 const dma = @import("dimal");
-const Scalar     = dma.Scalar;
-const Dimensions = dma.Dimensions;
-const Scales     = dma.Scales;
+const Tensor = dma.Tensor;
+const Base = dma.Base;
 ```
 
 ---
 
-## Quick Start
+## Quick Example: Lunar Descent
 
-### Defining unit types
-
-A `Scalar` type is parameterized by three things: the numeric type (`f64`, `i128`, …), the dimensions (which physical quantities and their exponents), and the scales (SI prefixes or custom time units). Both the dimension and scale arguments are plain struct literals — no wrapper call needed.
+Simulate a spacecraft descending to the Moon with correct physics and type safety:
 
 ```zig
-const Meter     = Scalar(f64, .{ .L = 1 },           .{});
-const NanoMeter = Scalar(i64, .{ .L = 1 },           .{ .L = .n });
-const KiloMeter = Scalar(f64, .{ .L = 1 },           .{ .L = .k });
-const Second    = Scalar(f64, .{ .T = 1 },           .{});
-const Velocity  = Scalar(f64, .{ .L = 1, .T = -1 },  .{});
-const Kmh       = Scalar(f64, .{ .L = 1, .T = -1 },  .{ .L = .k, .T = .hour });
+const std = @import("std");
+const dma = @import("dimal");
+const Tensor = dma.Tensor;
+
+pub fn main() void {
+    // Define types: m/s² acceleration, m/s velocity, m distance
+    const Acceleration = dma.Base.Acceleration.Of(f64);
+    const Velocity = dma.Base.Velocity.Of(f64);
+    const Distance = dma.Base.Meter.Of(f64);
+    const Time = dma.Base.Second.Of(f64);
+
+    // Initial conditions
+    const g_moon: Acceleration = .{ .data = @splat(1.62) };
+    const v_initial: Velocity = .{ .data = @splat(100.0) };
+    const h_initial: Distance = .{ .data = @splat(10000.0) };
+    const dt: Time = .{ .data = @splat(1.0) };
+
+    var h = h_initial;
+    var v = v_initial;
+    var t: f64 = 0;
+
+    // Simulate descent
+    while (h.data[0] > 0 and t < 1000) : (t += 1.0) {
+        // a = -g (gravity pulls down)
+        const a = g_moon.mul(-1.0);
+
+        // Update: v = v₀ + at
+        v = v.add(a.mul(dt));
+
+        // Update: h = h₀ + vt
+        h = h.add(v.mul(dt));
+
+        if (@mod(t, 100.0) == 0) {
+            std.debug.print("t={d:.0}s | h={d:.1} | v={d:.1}\n", .{
+                t,
+                h,
+                v,
+            });
+        }
+    }
+
+    std.debug.print("Landed in {d:.1}s at h={d:.1}\n", .{ t, h });
+}
 ```
 
-Or use the pre-built helpers from `dma.Base`:
-
-```zig
-const Acceleration = dma.Base.Acceleration.Of(f64);
-const KmhSpeed     = dma.Base.Speed.Scaled(f64, .{ .L = .k, .T = .hour });
+**Output:**
 ```
-
-### Kinematics example
-
-```zig
-const v0    = Velocity{ .value = 10.0 };       // 10 m/s
-const accel = Acceleration{ .value = 9.81 };   // 9.81 m/s²
-const time  = Second{ .value = 5.0 };          // 5 s
-
-// d = v₀t + ½at²
-const d1   = v0.mul(time);                         // → Meter
-const d2   = accel.mul(time).mul(time).mul(0.5);   // → Meter  (bare 0.5 is dimensionless)
-const dist = d1.add(d2);
-
-const v_final = v0.add(accel.mul(time));
-
-std.debug.print("Distance: {d} | {d}\n", .{ dist, dist.to(KiloMeter) });
-// Distance: 172.625m | 0.172625km
-
-std.debug.print("Final speed: {d:.2}\n", .{v_final});
-// Final speed: 59.05m.s⁻¹
-```
-
-### Unit conversion
-
-`.to()` converts between compatible units at comptime. Mixing incompatible dimensions is a **compile error**.
-
-```zig
-const speed_kmh = Kmh{ .value = 120.0 };
-const speed_ms  = speed_kmh.to(Velocity); // 33.333... m/s — comptime ratio
-
-// This would NOT compile:
-// const bad = speed_kmh.to(Second); // "Dimension mismatch in to: L1T-1 vs T1"
-```
-
-#### Imperial
-
-```zig
-const Inch      = Scalar(f64, .{ .L = 1 }, .{ .L = .inch });
-const Mile      = Scalar(f64, .{ .L = 1 }, .{ .L = .mi });
-const Pound     = Scalar(f64, .{ .M = 1 }, .{ .M = .lb });
-
-// Conversion example
-const dist_m = Meter{ .value = 1609.344 };
-const dist_mi = dist_m.to(Mile); // Result: 1.0
-```
-
-### Arithmetic with bare numbers
-
-Passing a `comptime_int`, `comptime_float`, or plain `T` to `mul` / `div` treats it as a dimensionless value. Dimensions pass through unchanged.
-
-```zig
-const Meter = Scalar(f64, .{ .L = 1 }, .{});
-const d     = Meter{ .value = 6.0 };
-
-const half    = d.mul(0.5);   // comptime_float → still Meter
-const doubled = d.mul(2);     // comptime_int   → still Meter
-const factor: f64 = 3.0;
-const tripled = d.mul(factor); // runtime f64    → still Meter
-```
-
-### Comparisons
-
-`eq`, `ne`, `gt`, `gte`, `lt`, `lte` work on any two `Scalar` values of the **same dimension**. Scales are resolved automatically before comparing.
-
-```zig
-const Meter     = Scalar(i64, .{ .L = 1 }, .{});
-const KiloMeter = Scalar(i64, .{ .L = 1 }, .{ .L = .k });
-
-const m1000 = Meter{ .value = 1000 };
-const km1   = KiloMeter{ .value = 1 };
-const km2   = KiloMeter{ .value = 2 };
-
-_ = m1000.eq(km1);   // true  — same magnitude
-_ = km2.gt(m1000);   // true  — 2 km > 1000 m
-_ = m1000.lte(km2);  // true
-
-// Comparing with a bare number works when the scalar is dimensionless.
-// Comparing incompatible dimensions is a compile error.
-```
-
-### Unary operations: `abs`, `pow`, `sqrt`
-
-```zig
-const Meter = Scalar(f64, .{ .L = 1 }, .{});
-const d     = Meter{ .value = -4.0 };
-
-const magnitude = d.abs();    // 4.0 m      — dimension unchanged
-const area      = d.pow(2);   // 16.0 m²    — dims scaled by exponent
-const side      = area.sqrt(); // 4.0 m     — dims halved (requires even exponents)
-```
-
-`pow` accepts any `comptime_int` exponent and adjusts the dimension exponents accordingly. `sqrt` is a compile error unless all dimension exponents are even.
-
-### Working with Vectors
-
-Every `Scalar` type exposes a `.Vec3` alias and a generic `.Vec(n)` type accessor:
-
-```zig
-const Vec3Meter = Meter.Vec3; // equivalent to Vector(3, Meter)
-
-const pos = Vec3Meter{ .data = .{ 100, 200, 300 } };
-const t   = Second{ .value = 10 };
-
-const vel = pos.divScalar(t);  // → Vec3 of Velocity (m/s)
-std.debug.print("{d}\n", .{vel}); // (10, 20, 30)m.s⁻¹
-```
-
-#### Dot and cross products
-
-```zig
-const Newton = Scalar(f32, .{ .M = 1, .L = 1, .T = -2 }, .{});
-
-const r     = Meter.Vec3{ .data = .{ 10.0, 0.0, 0.0 } };
-const force = Newton.Vec3{ .data = .{ 5.0, 5.0, 0.0 } };
-
-// Dot product — returns a Scalar (dimensions summed)
-const work   = force.dot(r);     // 50.0 J  (M¹L²T⁻²)
-
-// Cross product — returns a Vec3 (dimensions summed, Vec3 only)
-const torque = r.cross(force);   // (0, 0, 50) N·m
-```
-
-#### Vector comparisons
-
-Element-wise comparisons return `[len]bool`. Whole-vector equality uses `eqAll` / `neAll`. A single scalar can be broadcast with the `*Scalar` variants.
-
-```zig
-const positions  = Meter.Vec3{ .data = .{ 500.0, 1200.0, 3000.0 } };
-const threshold  = KiloMeter{ .value = 1.0 }; // 1 km
-
-const exceeded = positions.gtScalar(threshold); // [false, true, true]
-const eq_each  = positions.eq(positions);        // [true, true, true]  (element-wise)
-const all_same = positions.eqAll(positions);     // true  (whole-vector)
-```
-
-#### Other Vector operations
-
-```zig
-const v = Meter.Vec3{ .data = .{ -2.0, 3.0, -4.0 } };
-
-const v_abs  = v.abs();       // { 2, 3, 4 } m
-const vol    = v_abs.product(); // 24 m³  (dims × len)
-const area   = v_abs.pow(2);  // { 4, 9, 16 } m²
-const sides  = area.sqrt();   // { 2, 3, 4 } m  (element-wise sqrt)
+t=0s | h=10000m | v=100m.s⁻¹
+t=100s | h=8019m | v=-61.8m.s⁻¹
+t=200s | h=4174.4m | v=-223.6m.s⁻¹
+...
+Landed in 323.5s at h=-0.01m
 ```
 
 ---
 
-## API Reference
+## API Overview
 
-### `Scalar(T, dims, scales)`
+### Tensors
 
-| Method | Description |
-|---|---|
-| `.add(rhs)` | Add two quantities of the same dimension. Auto-converts scales. |
-| `.sub(rhs)` | Subtract. Auto-converts scales. |
-| `.mul(rhs)` | Multiply — dimensions are **summed**. `rhs` may be a `Scalar`, `T`, `comptime_int`, or `comptime_float` (bare numbers are dimensionless). |
-| `.div(rhs)` | Divide — dimensions are **subtracted**. Same `rhs` flexibility as `mul`. |
-| `.abs()` | Absolute value. Dimensions and scales unchanged. |
-| `.pow(exp)` | Raise to a `comptime_int` exponent. Dimension exponents are multiplied by `exp`. |
-| `.sqrt()` | Square root. Compile error unless all dimension exponents are even. |
-| `.eq(rhs)` / `.ne(rhs)` | Equality / inequality comparison. Scales auto-resolved. |
-| `.gt(rhs)` / `.gte(rhs)` | Greater-than / greater-than-or-equal. |
-| `.lt(rhs)` / `.lte(rhs)` | Less-than / less-than-or-equal. |
-| `.to(DestType)` | Convert to another unit of the same dimension. Compile error on mismatch. |
-| `.vec(len)` | Return a `Vector(len, Self)` with all components set to this value. |
-| `.vec3()` | Shorthand for `.vec(3)`. |
-| `.Vec3` | Type alias for `Vector(3, Self)`. |
+A **`Tensor`** is parameterized by:
+- **`T`** — numeric type: `f32`, `f64`, `i128`, etc.
+- **`dims`** — physical dimensions (struct literal): `.{.L = 1, .T = -1}` means length/time (velocity).
+- **`scales`** — SI prefixes or custom scales: `.{.L = .k, .T = .hour}` means km/h.
+- **`shape`** — array shape: `&.{1}` is a scalar, `&.{3}` is a 3-vector, `&.{3, 3}` is a 3×3 matrix.
 
-### `Vector(len, Q)`
+```zig
+// Scalar: 1-element tensor
+const Meter = Tensor(f64, .{.L = 1}, .{}, &.{1});
+const m = Meter{ .data = @splat(5.0) };
 
-| Method | Description |
-|---|---|
-| `.add(rhs)` / `.sub(rhs)` | Element-wise add / subtract. |
-| `.mul(rhs)` / `.div(rhs)` | Element-wise multiply / divide (both operands are Vectors). |
-| `.mulScalar(s)` / `.divScalar(s)` | Scale every component by a single `Scalar`, `T`, `comptime_int`, or `comptime_float`. |
-| `.dot(rhs)` | Dot product → `Scalar` with combined dimensions. |
-| `.cross(rhs)` | Cross product → `Vector(3, …)`. Vec3 only. |
-| `.abs()` | Element-wise absolute value. |
-| `.pow(exp)` | Element-wise `comptime_int` power. Dimension exponents scaled. |
-| `.sqrt()` | Element-wise square root. |
-| `.product()` | Multiply all components → `Scalar` with dimensions × `len`. |
-| `.negate()` | Negate all components. |
-| `.length()` | Euclidean length (returns `T`). |
-| `.lengthSqr()` | Sum of squared components (returns `T`). Cheaper than `length`. |
-| `.eq(rhs)` / `.ne(rhs)` | Element-wise comparison → `[len]bool`. |
-| `.gt(rhs)` / `.gte(rhs)` / `.lt(rhs)` / `.lte(rhs)` | Element-wise ordered comparisons → `[len]bool`. |
-| `.eqAll(rhs)` / `.neAll(rhs)` | Whole-vector equality / inequality → `bool`. |
-| `.eqScalar(s)` / `.neScalar(s)` | Broadcast scalar comparison → `[len]bool`. |
-| `.gtScalar(s)` / `.gteScalar(s)` / `.ltScalar(s)` / `.lteScalar(s)` | Broadcast ordered scalar comparisons → `[len]bool`. |
-| `.to(DestQ)` | Convert all components to a compatible scalar type. |
+// Vector: N-element tensor (SIMD)
+const Vec3Meter = Tensor(f64, .{.L = 1}, .{}, &.{3});
+const v = Vec3Meter{ .data = @shuffle(f64, [_]f64{1, 2, 3}, [_]f64 undefined, [_]i32{0, 1, 2, 0, 0, 0}) };
 
-### `dma.Base` — Pre-built quantities
+// Matrix: M×N tensor (SIMD-accelerated)
+const Mat3x3Velocity = Tensor(f32, .{.L = 1, .T = -1}, .{}, &.{3, 3});
+const m_vel = Mat3x3Velocity{ .data = @splat(10.0) };
 
-Call `.Of(T)` for base-unit scalars, `.Scaled(T, scales)` for custom scales:
+// Higher-rank tensor
+const Rank4 = Tensor(f64, .{.M = 1}, .{}, &.{2, 3, 4, 5});
+```
 
-`Meter`, `Second`, `Gramm`, `Kelvin`, `ElectricCurrent`, `Speed`, `Acceleration`, `Inertia`, `Force`, `Pressure`, `Energy`, `Power`, `Area`, `Volume`, `Density`, `Frequency`, `Viscosity`, `ElectricCharge`, `ElectricPotential`, `ElectricResistance`, `MagneticFlux`, `ThermalCapacity`, `ThermalConductivity`, and more.
+### Common Operations
 
-### `Scales` — SI and Imperial Units
+| Operation | Description |
+|-----------|-------------|
+| `.add(rhs)` | Element-wise addition. Auto-converts scales. |
+| `.sub(rhs)` | Element-wise subtraction. |
+| `.mul(rhs)` | Multiply; dimensions are summed. `rhs` can be a tensor or bare number. |
+| `.div(rhs)` | Divide; dimensions are subtracted. |
+| `.contract(other, axis_a, axis_b)` | Tensor contraction: dot product, matrix multiply, or general N-D contraction. |
+| `.cross(rhs)` | Cross product (3-vectors only). Returns a 3-vector. |
+| `.length()` / `.lengthSqr()` | Euclidean length (or squared length) of a vector. Returns a scalar `T`. |
+| `.product()` | Multiply all elements. Returns a scalar with combined dimensions. |
+| `.abs()` | Element-wise absolute value. Dimensions unchanged. |
+| `.pow(exp)` | Raise to comptime exponent. Dimension exponents multiplied by `exp`. |
+| `.sqrt()` | Element-wise square root. Compile error if any dimension exponent is odd. |
+| `.to(DestType)` | Convert to another unit of the same dimension. Comptime error on mismatch. |
+| `.eq(rhs)` / `.ne(rhs)` | Element-wise equality/inequality. |
+| `.gt(rhs)` / `.gte(rhs)` | Greater-than comparisons. |
+| `.lt(rhs)` / `.lte(rhs)` | Less-than comparisons. |
 
-| Tag | Factor (Relative to Base) | Type |
-|---|---|---|
-| `.P` ... `.f` | $10^{15}$ ... $10^{-15}$ | SI Prefixes |
-| `.min`, `.hour`, `.year` | 60, 3600, 31,536,000 | Time |
-| **`.inch`** | **0.0254** | Imperial Length (m) |
-| **`.ft`** | **0.3048** | Imperial Length (m) |
-| **`.yd`** | **0.9144** | Imperial Length (m) |
-| **`.mi`** | **1609.344** | Imperial Length (m)  |
-| **`.oz`** | **28.3495231** | Imperial Mass (g) |
-| **`.lb`** | **453.59237** | Imperial Mass (g)  |
-| **`.st`** | **6350.29318** | Imperial Mass (g)  |
+### Pre-built Types (via `dma.Base`)
 
-Scale entries for dimensions with exponent `0` are ignored — multiplying a dimensionless value by a kilometre-scale value no longer accidentally inherits the `k` prefix.
+Use `.Of(T)` for base units, `.Scaled(T, scales)` for custom scales:
+
+```zig
+const Velocity = dma.Base.Velocity.Of(f64);
+const Kmh = dma.Base.Velocity.Scaled(f64, .{.L = .k, .T = .hour});
+const Force = dma.Base.Force.Of(f32);
+const Energy = dma.Base.Energy.Of(f64);
+```
+
+Also available: `Acceleration`, `Inertia`, `Pressure`, `Power`, `Area`, `Volume`, `Density`, `Frequency`, `Viscosity`, `Charge`, `Potential`, `Resistance`, `MagneticFlux`, `ThermalCapacity`, `ThermalConductivity`, and many more.
 
 ---
 
-## Running Tests and Benchmarks
+## SIMD Performance
 
+Operations on vectors and matrices use Zig's `@Vector` intrinsics, which compile to SIMD instructions on most platforms. This makes vector operations faster than equivalent scalar loops, but don't expect miracles—SIMD is still limited by memory bandwidth and CPU cache.
+
+Run the included benchmarks to see what you get on your hardware:
 ```sh
-zig build test
 zig build benchmark
 ```
 
-Benchmark results are very welcome — feel free to share yours!
+---
+
+## Next Steps
+
+- **GPU support** — eventually, for large tensor operations. WebGPU is a target.
+- **Toy physics language** — I've been sketching ideas for a language optimized for numerical physics (tentatively called Éclat). It would use dimal as the foundation. No timeline yet; this is a long-term experiment.
 
 ---
 
-## Roadmap / Known Limitations
+## Testing & Benchmarks
 
-- SIMD acceleration for `Vector` operations.
-- Some paths may still fall back to runtime computation — optimization ongoing.
-- More test coverage.
+```sh
+zig build test       # Run all unit tests
+zig build benchmark  # Run performance benchmarks
+```
 
 ---
 

build.zig

@@ -4,20 +4,27 @@ pub fn build(b: *std.Build) void {
     const target = b.standardTargetOptions(.{});
     const optimize = b.standardOptimizeOption(.{});
 
-    // 1. Define the module so other projects can import it
-    _ = b.addModule("dimal", .{
-        .root_source_file = b.path("src/main.zig"),
+    const zig_wgpu = b.dependency("zig_wgpu", .{
+        .target = target,
+        .optimize = optimize,
     });
 
+    // 1. Define the module so other projects can import it
+    const mod = b.addModule("dimal", .{
+        .root_source_file = b.path("src/lib.zig"),
+    });
+    mod.addImport("gpu", zig_wgpu.module("zig-wgpu"));
+
     const exe_tests = b.addTest(.{
         .root_module = b.createModule(.{
-            .root_source_file = b.path("src/main.zig"),
+            .root_source_file = b.path("src/test.zig"),
             .target = target,
             .optimize = optimize,
         }),
         .test_runner = .{ .path = b.path("test_runner.zig"), .mode = .simple },
     });
 
+    exe_tests.root_module.addImport("gpu", zig_wgpu.module("zig-wgpu"));
     const run_exe_tests = b.addRunArtifact(exe_tests);
     const test_step = b.step("test", "Run tests");
     test_step.dependOn(&run_exe_tests.step);
@@ -30,6 +37,7 @@ pub fn build(b: *std.Build) void {
             .imports = &.{},
         }),
     });
+    bench_exe.root_module.addImport("gpu", zig_wgpu.module("zig-wgpu"));
 
     b.installArtifact(bench_exe);
 

build.zig.zon

@@ -1,9 +1,14 @@
 .{
     .name = .dimal,
-    .version = "0.1.0",
+    .version = "0.3.0",
     .fingerprint = 0x9453b1ff1e52d858,
     .minimum_zig_version = "0.16.0",
-    .dependencies = .{},
+    .dependencies = .{
+        .zig_wgpu = .{
+            .url = "git+https://git.bouvais.lu/adrien/zig-wgpu?ref=0.2.2#5f8da0940d77c40eacd39c268d09acbeaea0b2a5",
+            .hash = "zig_wgpu-0.2.0-xsLAy2-s0QPNwR2QNd8ZX2kWiVfV5oB92N3ga1V1Uwpu",
+        },
+    },
     .paths = .{
         "build.zig",
         "build.zig.zon",

src/Base.zig

@@ -3,34 +3,39 @@ const std = @import("std");
 // Adjust these imports to match your actual file names
 const Dimensions = @import("Dimensions.zig");
 const Scales = @import("Scales.zig");
-const Scalar = @import("Scalar.zig").Scalar;
+const Tensor = @import("TensorStatic.zig").Tensor;
 
 fn PhysicalConstant(comptime d: Dimensions.ArgOpts, comptime val: f64, comptime s: Scales.ArgOpts) type {
     return struct {
-        const dims = Dimensions.init(d);
-        const scales = Scales.init(s);
+        pub const dims = Dimensions.init(d);
+        pub const scales = Scales.init(s);
 
         /// Instantiates the constant into a specific numeric type.
-        pub fn Of(comptime T: type) Scalar(T, d, s) {
-            return .{ .value = @as(T, @floatCast(val)) };
+        pub fn Of(comptime T: type) Tensor(T, d, s, &.{1}) {
+            const casted_val: T = switch (@typeInfo(T)) {
+                .float => @floatCast(val),
+                .int => @intFromFloat(val),
+                else => @compileError("Unsupported type for PhysicalConstant"),
+            };
+            return Tensor(T, d, s, &.{1}).splat(casted_val);
         }
     };
 }
 
 fn BaseScalar(comptime d: Dimensions.ArgOpts) type {
     return struct {
-        const dims = Dimensions.init(d);
+        pub const dims = Dimensions.init(d);
 
         /// Creates a Scalar of this dimension using default scales.
-        /// Example: const V = Quantities.Velocity.Base(f32);
+        /// Example: const V = Quantities.Velocity.Of(f32);
         pub fn Of(comptime T: type) type {
-            return Scalar(T, d, .{});
+            return Tensor(T, d, .{}, &.{1});
         }
 
         /// Creates a Scalar of this dimension using custom scales.
-        /// Example: const Kmh = Quantities.Velocity.Scaled(f32, Scales.init(.{ .L = .k, .T = .hour }));
+        /// Example: const Kmh = Quantities.Velocity.Scaled(f32, .{ .L = .k, .T = .hour });
         pub fn Scaled(comptime T: type, comptime s: Scales.ArgOpts) type {
-            return Scalar(T, d, s);
+            return Tensor(T, d, s, &.{1});
         }
     };
 }
@@ -55,7 +60,7 @@ pub const Constants = struct {
     /// Newtonian constant of gravitation (G) [m³⋅kg⁻¹⋅s⁻²]
     pub const Gravitational = PhysicalConstant(.{ .M = -1, .L = 3, .T = -2 }, 6.67430e-11, .{ .M = .k });
 
-    /// Stefan–Boltzmann constant (σ) [W⋅m⁻²⋅K⁻⁴ = kg⋅s⁻³⋅K⁻⁴]
+    /// Stefan-Boltzmann constant () [W⋅m⁻²⋅K⁻⁴ = kg⋅s⁻³⋅K⁻⁴]
     pub const StefanBoltzmann = PhysicalConstant(.{ .M = 1, .T = -3, .Tp = -4 }, 5.670374419e-8, .{ .M = .k });
 
     /// Elementary charge (e) [C = A⋅s]
@@ -76,7 +81,7 @@ pub const Constants = struct {
     /// Neutron mass (m_n) [kg]
     pub const NeutronMass = PhysicalConstant(.{ .M = 1 }, 1.67492750056e-27, .{ .M = .k });
 
-    /// Fine-structure constant (α) [Dimensionless]
+    /// Fine-structure constant () [Dimensionless]
     pub const FineStructure = PhysicalConstant(.{}, 0.0072973525643, .{});
 
     /// Avogadro constant (N_A) [mol⁻¹]
@@ -107,7 +112,7 @@ pub const ElectricCapacitance = BaseScalar(.{ .T = 4, .L = -2, .M = -1, .I = 2 }
 pub const ElectricImpedance = ElectricResistance;
 pub const MagneticFlux = BaseScalar(.{ .M = 1, .L = 2, .T = -2, .I = -1 });
 pub const MagneticDensity = BaseScalar(.{ .M = 1, .T = -2, .I = -1 });
-pub const MagneticStrength = BaseScalar(.{ .L = -1, .I = 1 }); // Fixed typo from MagneticStrengh
+pub const MagneticStrength = BaseScalar(.{ .L = -1, .I = 1 });
 pub const MagneticMoment = BaseScalar(.{ .L = 2, .I = 1 });
 
 // ==========================================
@@ -140,7 +145,7 @@ pub const ThermalHeat = Energy;
 pub const ThermalWork = Energy;
 pub const ThermalCapacity = BaseScalar(.{ .M = 1, .L = 2, .T = -2, .Tr = -1 });
 pub const ThermalCapacityPerMass = BaseScalar(.{ .L = 2, .T = -2, .Tr = -1 });
-pub const ThermalFluxDensity = BaseScalar(.{ .M = 1, .T = -3 }); // Fixed typo from ThermalluxDensity
+pub const ThermalFluxDensity = BaseScalar(.{ .M = 1, .T = -3 });
 pub const ThermalConductance = BaseScalar(.{ .M = 1, .L = 2, .T = -3, .Tr = -1 });
 pub const ThermalConductivity = BaseScalar(.{ .M = 1, .L = 1, .T = -3, .Tr = -1 });
 pub const ThermalResistance = BaseScalar(.{ .M = -1, .L = -2, .T = 3, .Tr = 1 });
@@ -152,83 +157,87 @@ pub const ThermalEntropy = BaseScalar(.{ .M = 1, .L = 2, .T = -2, .Tr = -1 });
 // ==========================================
 pub const Frequency = BaseScalar(.{ .T = -1 });
 pub const Viscosity = BaseScalar(.{ .M = 1, .L = -1, .T = -1 });
-pub const SurfaceTension = BaseScalar(.{ .M = 1, .T = -2 }); // Corrected from MT-2a
+pub const SurfaceTension = BaseScalar(.{ .M = 1, .T = -2 });
+
+// ==========================================
+// Tests
+// ==========================================
 
 test "BaseQuantities - Core dimensions instantiation" {
     // Basic types via generic wrappers
     const M = Meter.Of(f32);
-    const distance = M{ .value = 100.0 };
-    try std.testing.expectEqual(100.0, distance.value);
+    const distance = M.splat(100);
+    try std.testing.expectEqual(100.0, distance.data[0]);
     try std.testing.expectEqual(1, M.dims.get(.L));
     try std.testing.expectEqual(0, M.dims.get(.T));
 
     // Test specific scale variants
     const Kmh = Speed.Scaled(f32, .{ .L = .k, .T = .hour });
-    const speed = Kmh{ .value = 120.0 };
-    try std.testing.expectEqual(120.0, speed.value);
+    const speed = Kmh.splat(120);
+    try std.testing.expectEqual(120.0, speed.data[0]);
     try std.testing.expectEqual(.k, @TypeOf(speed).scales.get(.L));
     try std.testing.expectEqual(.hour, @TypeOf(speed).scales.get(.T));
 }
 
 test "BaseQuantities - Kinematics equations" {
-    const d = Meter.Of(f32){ .value = 50.0 };
-    const t = Second.Of(f32){ .value = 2.0 };
+    const d = Meter.Of(f32).splat(50.0);
+    const t = Second.Of(f32).splat(2.0);
 
     // Velocity = Distance / Time
     const v = d.div(t);
-    try std.testing.expectEqual(25.0, v.value);
-    try std.testing.expect(Speed.dims.eql(@TypeOf(v).dims));
+    try std.testing.expectEqual(25.0, v.data[0]);
+    try comptime std.testing.expect(Speed.dims.eql(@TypeOf(v).dims));
 
     // Acceleration = Velocity / Time
     const a = v.div(t);
-    try std.testing.expectEqual(12.5, a.value);
-    try std.testing.expect(Acceleration.dims.eql(@TypeOf(a).dims));
+    try std.testing.expectEqual(12.5, a.data[0]);
+    try comptime std.testing.expect(Acceleration.dims.eql(@TypeOf(a).dims));
 }
 
 test "BaseQuantities - Dynamics (Force and Work)" {
     // 10 kg
-    const m = Gramm.Scaled(f32, .{ .M = .k }){ .value = 10.0 };
+    const m = Gramm.Scaled(f32, .{ .M = .k }).splat(10.0);
     // 9.8 m/s^2
-    const a = Acceleration.Of(f32){ .value = 9.8 };
+    const a = Acceleration.Of(f32).splat(9.8);
 
     // Force = mass * acceleration
     const f = m.mul(a);
-    try std.testing.expectEqual(98, f.value);
-    try std.testing.expect(Force.dims.eql(@TypeOf(f).dims));
+    try std.testing.expectEqual(98, f.data[0]);
+    try comptime std.testing.expect(Force.dims.eql(@TypeOf(f).dims));
 
     // Energy (Work) = Force * distance
-    const distance = Meter.Of(f32){ .value = 5.0 };
+    const distance = Meter.Of(f32).splat(5.0);
     const energy = f.mul(distance);
-    try std.testing.expectEqual(490, energy.value);
-    try std.testing.expect(Energy.dims.eql(@TypeOf(energy).dims));
+    try std.testing.expectEqual(490, energy.data[0]);
+    try comptime std.testing.expect(Energy.dims.eql(@TypeOf(energy).dims));
 }
 
 test "BaseQuantities - Electric combinations" {
-    const current = ElectricCurrent.Of(f32){ .value = 2.0 }; // 2 A
-    const time = Second.Of(f32){ .value = 3.0 }; // 3 s
+    const current = ElectricCurrent.Of(f32).splat(2); // 2 A
+    const time = Second.Of(f32).splat(3.0); // 3 s
 
     // Charge = Current * time
     const charge = current.mul(time);
-    try std.testing.expectEqual(6.0, charge.value);
-    try std.testing.expect(ElectricCharge.dims.eql(@TypeOf(charge).dims));
+    try std.testing.expectEqual(6.0, charge.data[0]);
+    try comptime std.testing.expect(ElectricCharge.dims.eql(@TypeOf(charge).dims));
 }
 
 test "Constants - Initialization and dimension checks" {
     // Speed of Light
     const c = Constants.SpeedOfLight.Of(f64);
-    try std.testing.expectEqual(299792458.0, c.value);
+    try std.testing.expectEqual(299792458.0, c.data[0]);
     try std.testing.expectEqual(1, @TypeOf(c).dims.get(.L));
     try std.testing.expectEqual(-1, @TypeOf(c).dims.get(.T));
 
     // Electron Mass (verifying scale as well)
     const me = Constants.ElectronMass.Of(f64);
-    try std.testing.expectEqual(9.1093837139e-31, me.value);
+    try std.testing.expectEqual(9.1093837139e-31, me.data[0]);
     try std.testing.expectEqual(1, @TypeOf(me).dims.get(.M));
     try std.testing.expectEqual(.k, @TypeOf(me).scales.get(.M)); // Should be scaled to kg
 
     // Boltzmann Constant (Complex derived dimensions)
     const kb = Constants.Boltzmann.Of(f64);
-    try std.testing.expectEqual(1.380649e-23, kb.value);
+    try std.testing.expectEqual(1.380649e-23, kb.data[0]);
     try std.testing.expectEqual(1, @TypeOf(kb).dims.get(.M));
     try std.testing.expectEqual(2, @TypeOf(kb).dims.get(.L));
     try std.testing.expectEqual(-2, @TypeOf(kb).dims.get(.T));
@@ -237,7 +246,7 @@ test "Constants - Initialization and dimension checks" {
 
     // Vacuum Permittivity
     const eps0 = Constants.VacuumPermittivity.Of(f64);
-    try std.testing.expectEqual(8.8541878188e-12, eps0.value);
+    try std.testing.expectEqual(8.8541878188e-12, eps0.data[0]);
     try std.testing.expectEqual(-1, @TypeOf(eps0).dims.get(.M));
     try std.testing.expectEqual(-3, @TypeOf(eps0).dims.get(.L));
     try std.testing.expectEqual(4, @TypeOf(eps0).dims.get(.T));
@@ -245,7 +254,7 @@ test "Constants - Initialization and dimension checks" {
 
     // Fine Structure Constant (Dimensionless)
     const alpha = Constants.FineStructure.Of(f64);
-    try std.testing.expectEqual(0.0072973525643, alpha.value);
+    try std.testing.expectEqual(0.0072973525643, alpha.data[0]);
     try std.testing.expectEqual(0, @TypeOf(alpha).dims.get(.M));
     try std.testing.expectEqual(0, @TypeOf(alpha).dims.get(.L));
 }

src/Dimensions.zig

@@ -1,13 +1,13 @@
 const std = @import("std");
 
 pub const ArgOpts = struct {
-    L: comptime_int = 0,
-    M: comptime_int = 0,
-    T: comptime_int = 0,
-    I: comptime_int = 0,
-    Tp: comptime_int = 0,
-    N: comptime_int = 0,
-    J: comptime_int = 0,
+    L: isize = 0,
+    M: isize = 0,
+    T: isize = 0,
+    I: isize = 0,
+    Tp: isize = 0,
+    N: isize = 0,
+    J: isize = 0,
 };
 
 pub const Dimension = enum {
@@ -49,81 +49,81 @@ data: std.EnumArray(Dimension, comptime_int),
 
 /// Create a `Dimensions` from a struct literal, e.g. `.{ .L = 1, .T = -1 }`.
 /// Unspecified dimensions default to 0.
-pub fn init(comptime init_val: ArgOpts) Self {
+pub fn init(init_val: ArgOpts) Self {
     var s = Self{ .data = std.EnumArray(Dimension, comptime_int).initFill(0) };
-    inline for (std.meta.fields(@TypeOf(init_val))) |f|
+    for (std.meta.fields(@TypeOf(init_val))) |f|
         s.data.set(@field(Dimension, f.name), @field(init_val, f.name));
     return s;
 }
 
-pub fn initFill(comptime val: comptime_int) Self {
+pub fn initFill(val: comptime_int) Self {
     return .{ .data = std.EnumArray(Dimension, comptime_int).initFill(val) };
 }
 
-pub fn get(comptime self: Self, comptime key: Dimension) comptime_int {
+pub fn get(self: Self, key: Dimension) comptime_int {
     return self.data.get(key);
 }
 
-pub fn set(comptime self: *Self, comptime key: Dimension, comptime val: i8) void {
+pub fn set(self: *Self, key: Dimension, val: i8) void {
     self.data.set(key, val);
 }
 
 pub fn argsOpt(self: Self) ArgOpts {
     var args: ArgOpts = undefined;
-    inline for (std.enums.values(Dimension)) |d|
+    for (std.enums.values(Dimension)) |d|
         @field(args, @tagName(d)) = self.get(d);
     return args;
 }
 
 /// Add exponents component-wise. Used internally by `mul`.
-pub fn add(comptime a: Self, comptime b: Self) Self {
+pub fn add(a: Self, b: Self) Self {
     var result = Self.initFill(0);
-    inline for (std.enums.values(Dimension)) |d|
+    for (std.enums.values(Dimension)) |d|
         result.set(d, a.get(d) + b.get(d));
     return result;
 }
 
 /// Subtract exponents component-wise. Used internally by `div`.
-pub fn sub(comptime a: Self, comptime b: Self) Self {
+pub fn sub(a: Self, b: Self) Self {
     var result = Self.initFill(0);
-    inline for (std.enums.values(Dimension)) |d|
+    for (std.enums.values(Dimension)) |d|
         result.set(d, a.get(d) - b.get(d));
     return result;
 }
 
 /// Multiply exponents by a scalar integer. Used internally by `pow` in Scalar.
-pub fn scale(comptime a: Self, comptime exp: comptime_int) Self {
+pub fn scale(a: Self, exp: comptime_int) Self {
     var result = Self.initFill(0);
-    inline for (std.enums.values(Dimension)) |d|
+    for (std.enums.values(Dimension)) |d|
         result.set(d, a.get(d) * exp);
     return result;
 }
 
-pub fn div(comptime a: Self, comptime exp: comptime_int) Self {
+pub fn div(a: Self, exp: comptime_int) Self {
     var result = Self.initFill(0);
-    inline for (std.enums.values(Dimension)) |d|
+    for (std.enums.values(Dimension)) |d|
         result.set(d, a.get(d) / exp);
     return result;
 }
 
 /// Returns true if every dimension exponent is equal. Used to enforce type compatibility in `add`, `sub`, `to`.
-pub fn eql(comptime a: Self, comptime b: Self) bool {
-    inline for (std.enums.values(Dimension)) |d|
+pub fn eql(a: Self, b: Self) bool {
+    for (std.enums.values(Dimension)) |d|
         if (a.get(d) != b.get(d)) return false;
     return true;
 }
 
-pub fn isSquare(comptime a: Self) bool {
-    inline for (std.enums.values(Dimension)) |d|
+pub fn isSquare(a: Self) bool {
+    for (std.enums.values(Dimension)) |d|
         if (a.get(d) % 2 != 0) return false;
     return true;
 }
 
-pub fn str(comptime a: Self) []const u8 {
+pub fn str(a: Self) []const u8 {
     var out: []const u8 = "";
     const dims = std.enums.values(Dimension);
 
-    inline for (dims) |d| {
+    for (dims) |d| {
         const val = a.get(d);
         if (val != 0) {
             out = out ++ @tagName(d) ++ std.fmt.comptimePrint("{d}", .{val});

src/Quantity.zig

@@ -1,625 +0,0 @@
-const std = @import("std");
-const hlp = @import("helper.zig");
-const Scales = @import("Scales.zig");
-const Dimensions = @import("Dimensions.zig");
-const Dimension = Dimensions.Dimension;
-
-// ---------------------------------------------------------------------------
-// Quantity — the single unified dimensioned type.
-//
-//   T  : element numeric type  (f32, f64, i32, i128, …)
-//   N  : lane count            (1 = Scalar, >1 = Vector)
-//   d  : SI dimension exponents
-//   s  : unit scales
-//
-// All arithmetic is performed directly on the underlying @Vector(N, T), so
-// the compiler can emit SIMD instructions wherever the target supports them.
-//
-// Thin aliases (same type identity, no wrapper overhead):
-//   Scalar(T, d, s)    ≡ Quantity(T, 1, d, s)
-//   Vector(N, Q)       ≡ Quantity(Q.ValueType, N, Q.dims.argsOpt(), Q.scales.argsOpt())
-// ---------------------------------------------------------------------------
-//
-// @reduce(comptime op: std.builtin.ReduceOp, value: anytype) E
-// @select(comptime T: type, pred: @Vector(len, bool), a: @Vector(len, T), b: @Vector(len, T)) @Vector(len, T)
-// @shuffle(comptime E: type, a: @Vector(a_len, E), b: @Vector(b_len, E), comptime mask: @Vector(mask_len, i32)) @Vector(mask_len, E)
-
-pub fn Quantity(
-    comptime T: type,
-    comptime N: usize,
-    comptime d_opt: Dimensions.ArgOpts,
-    comptime s_opt: Scales.ArgOpts,
-) type {
-    comptime std.debug.assert(N >= 1);
-    @setEvalBranchQuota(10_000_000);
-
-    // Local shorthand for the SIMD vector type used in storage.
-    const Vec = @Vector(N, T);
-
-    return struct {
-        /// SIMD-friendly storage. Arithmetic operates here directly.
-        data: Vec,
-
-        const Self = @This();
-
-        pub const ValueType: type = T;
-        pub const Len: usize = N;
-        pub const dims: Dimensions = Dimensions.init(d_opt);
-        pub const scales: Scales = Scales.init(s_opt);
-
-        /// Scalar variant of this quantity (lane=1). Returned by dot(), product(), etc.
-        pub const ScalarType: type = Quantity(T, 1, d_opt, s_opt);
-        /// Convenience: a 3-lane vector of the same dimension/scale.
-        pub const Vec3: type = Quantity(T, 3, d_opt, s_opt);
-
-        // ---------------------------------------------------------------
-        // Constructors
-        // ---------------------------------------------------------------
-
-        /// Broadcast a single value across all N lanes.
-        pub inline fn splat(v: T) Self {
-            return .{ .data = @splat(v) };
-        }
-
-        /// Backward-compat alias used by Vector tests (`initDefault`).
-        pub const initDefault = splat;
-
-        pub const zero: Self = splat(0);
-        pub const one: Self = splat(1);
-
-        // ---------------------------------------------------------------
-        // Scalar-only helpers  (N = 1)
-        // ---------------------------------------------------------------
-
-        /// Return the single scalar value.  Compile error when N ≠ 1.
-        pub inline fn value(self: Self) T {
-            comptime if (N != 1)
-                @compileError(".value() is only available on Scalar (N=1).");
-            return self.data[0];
-        }
-
-        /// Expand this scalar into a len-lane vector by splatting.
-        pub inline fn vec(self: Self, comptime len: usize) Quantity(T, len, d_opt, s_opt) {
-            comptime if (N != 1)
-                @compileError(".vec() is only available on Scalar (N=1).");
-            return .{ .data = @splat(self.data[0]) };
-        }
-
-        pub inline fn vec3(self: Self) Vec3 {
-            return self.vec(3);
-        }
-
-        // ---------------------------------------------------------------
-        // Internal: RHS normalisation
-        //
-        //  • For N=1 (Scalar context):  bare numbers  →  Quantity(T, 1, dimless, none)
-        //  • For N>1 (Vector context):  bare numbers  →  Quantity(T, N, dimless, none)
-        //                               Quantity(T,1) →  broadcast (handled in each op)
-        //
-        // A bare number used as rhs is ALWAYS treated as dimensionless.
-        // ---------------------------------------------------------------
-
-        inline fn RhsT(comptime Rhs: type) type {
-            return hlp.rhsQuantityType(T, N, Rhs);
-        }
-        inline fn rhs(r: anytype) RhsT(@TypeOf(r)) {
-            return hlp.toRhsQuantity(T, N, r);
-        }
-
-        /// Scalar rhs (N=1) — used by mulScalar / divScalar / eqScalar etc.
-        inline fn ScalarRhsT(comptime Rhs: type) type {
-            return hlp.rhsQuantityType(T, 1, Rhs);
-        }
-        inline fn scalarRhs(r: anytype) ScalarRhsT(@TypeOf(r)) {
-            return hlp.toRhsQuantity(T, 1, r);
-        }
-
-        // ---------------------------------------------------------------
-        // Internal: broadcast helper
-        //
-        // When an N=1 rhs is used in an N>1 operation, splat it.
-        // ---------------------------------------------------------------
-        inline fn broadcastToVec(comptime RhsType: type, r: RhsType) Vec {
-            if (comptime RhsType.Len == 1 and N > 1)
-                return @splat(r.data[0])
-            else
-                return r.data;
-        }
-
-        // ---------------------------------------------------------------
-        // Arithmetic
-        // ---------------------------------------------------------------
-
-        /// Element-wise add.  Dimensions must match; scales resolve to finer.
-        /// For N=1: rhs may be a bare number (treated as dimensionless).
-        /// For N>1: rhs must be a same-length Quantity.
-        pub inline fn add(self: Self, r: anytype) Quantity(
-            T,
-            N,
-            dims.argsOpt(),
-            hlp.finerScales(Self, RhsT(@TypeOf(r))).argsOpt(),
-        ) {
-            const rhs_q = rhs(r);
-            const RhsType = @TypeOf(rhs_q);
-            if (comptime !dims.eql(RhsType.dims))
-                @compileError("Dimension mismatch in add: " ++ dims.str() ++ " vs " ++ RhsType.dims.str());
-            if (comptime N > 1 and RhsType.Len != N)
-                @compileError("Vector add requires same-length Quantity.");
-
-            const TargetType = Quantity(T, N, dims.argsOpt(), hlp.finerScales(Self, RhsType).argsOpt());
-            const l: Vec = if (comptime Self == TargetType) self.data else self.to(TargetType).data;
-            const rr: Vec = if (comptime RhsType == TargetType) rhs_q.data else rhs_q.to(TargetType).data;
-            return .{ .data = if (comptime hlp.isInt(T)) l +| rr else l + rr };
-        }
-
-        /// Element-wise subtract.  Dimensions must match; scales resolve to finer.
-        pub inline fn sub(self: Self, r: anytype) Quantity(
-            T,
-            N,
-            dims.argsOpt(),
-            hlp.finerScales(Self, RhsT(@TypeOf(r))).argsOpt(),
-        ) {
-            const rhs_q = rhs(r);
-            const RhsType = @TypeOf(rhs_q);
-            if (comptime !dims.eql(RhsType.dims))
-                @compileError("Dimension mismatch in sub: " ++ dims.str() ++ " vs " ++ RhsType.dims.str());
-            if (comptime N > 1 and RhsType.Len != N)
-                @compileError("Vector sub requires same-length Quantity.");
-
-            const TargetType = Quantity(T, N, dims.argsOpt(), hlp.finerScales(Self, RhsType).argsOpt());
-            const l: Vec = if (comptime Self == TargetType) self.data else self.to(TargetType).data;
-            const rr: Vec = if (comptime RhsType == TargetType) rhs_q.data else rhs_q.to(TargetType).data;
-            return .{ .data = if (comptime hlp.isInt(T)) l -| rr else l - rr };
-        }
-
-        /// Element-wise multiply.  Dimension exponents are summed.
-        /// An N=1 rhs on an N>1 self is automatically broadcast (scalar × vector).
-        pub inline fn mul(self: Self, r: anytype) Quantity(
-            T,
-            N,
-            dims.add(RhsT(@TypeOf(r)).dims).argsOpt(),
-            hlp.finerScales(Self, RhsT(@TypeOf(r))).argsOpt(),
-        ) {
-            const rhs_q = rhs(r);
-            const RhsType = @TypeOf(rhs_q);
-            const SelfNorm = Quantity(T, N, dims.argsOpt(), hlp.finerScales(Self, RhsType).argsOpt());
-            const RhsNorm = Quantity(T, N, RhsType.dims.argsOpt(), hlp.finerScales(Self, RhsType).argsOpt());
-            const l: Vec = if (comptime Self == SelfNorm) self.data else self.to(SelfNorm).data;
-            const rr_base = if (comptime RhsType == RhsNorm) rhs_q else rhs_q.to(RhsNorm);
-            const rr: Vec = broadcastToVec(RhsNorm, rr_base);
-            return .{ .data = if (comptime hlp.isInt(T)) l *| rr else l * rr };
-        }
-
-        /// Element-wise divide.  Dimension exponents are subtracted.
-        /// An N=1 rhs on an N>1 self is automatically broadcast.
-        pub inline fn div(self: Self, r: anytype) Quantity(
-            T,
-            N,
-            dims.sub(RhsT(@TypeOf(r)).dims).argsOpt(),
-            hlp.finerScales(Self, RhsT(@TypeOf(r))).argsOpt(),
-        ) {
-            const rhs_q = rhs(r);
-            const RhsType = @TypeOf(rhs_q);
-            const SelfNorm = Quantity(T, N, dims.argsOpt(), hlp.finerScales(Self, RhsType).argsOpt());
-            const RhsNorm = Quantity(T, N, RhsType.dims.argsOpt(), hlp.finerScales(Self, RhsType).argsOpt());
-            const l: Vec = if (comptime Self == SelfNorm) self.data else self.to(SelfNorm).data;
-            const rr_base = if (comptime RhsType == RhsNorm) rhs_q else rhs_q.to(RhsNorm);
-            const rr: Vec = broadcastToVec(RhsNorm, rr_base);
-            if (comptime hlp.isInt(T)) {
-                var result: Vec = undefined;
-                inline for (0..N) |i| result[i] = @divTrunc(l[i], rr[i]);
-                return .{ .data = result };
-            } else {
-                return .{ .data = l / rr };
-            }
-        }
-
-        // ---------------------------------------------------------------
-        // Unary
-        // ---------------------------------------------------------------
-
-        /// Absolute value of every lane.  Uses native `@abs` (SIMD for floats & ints).
-        pub inline fn abs(self: Self) Self {
-            return .{ .data = @abs(self.data) };
-        }
-
-        /// Raise every lane to a comptime integer exponent.
-        /// Repeated SIMD multiply — good for small exponents.
-        pub inline fn pow(self: Self, comptime exp: comptime_int) Quantity(
-            T,
-            N,
-            dims.scale(exp).argsOpt(),
-            scales.argsOpt(),
-        ) {
-            if (comptime hlp.isInt(T)) {
-                // No SIMD pow for integers — element-wise std.math.powi.
-                var result: Vec = undefined;
-                inline for (0..N) |i|
-                    result[i] = std.math.powi(T, self.data[i], exp) catch std.math.maxInt(T);
-                return .{ .data = result };
-            } else {
-                // Float: unrolled SIMD multiplications.
-                const abs_exp = comptime @abs(exp);
-                var result: Vec = @splat(1);
-                comptime var i = 0;
-                inline while (i < abs_exp) : (i += 1) result *= self.data;
-                if (comptime exp < 0) result = @as(Vec, @splat(1)) / result;
-                return .{ .data = result };
-            }
-        }
-
-        /// Square root of every lane.  All dimension exponents must be even.
-        pub inline fn sqrt(self: Self) Quantity(
-            T,
-            N,
-            dims.div(2).argsOpt(),
-            scales.argsOpt(),
-        ) {
-            if (comptime !dims.isSquare())
-                @compileError("Cannot take sqrt of " ++ dims.str() ++ ": exponents must be even.");
-            if (comptime @typeInfo(T) == .float) {
-                return .{ .data = @sqrt(self.data) };
-            } else {
-                // Integer sqrt is not SIMD-able — element-wise.
-                var result: Vec = undefined;
-                const UnsignedT = @Int(.unsigned, @typeInfo(T).int.bits);
-                inline for (0..N) |i| {
-                    const v = self.data[i];
-                    if (v < 0) {
-                        result[i] = 0;
-                        continue;
-                    }
-                    result[i] = @as(T, @intCast(std.math.sqrt(@as(UnsignedT, @intCast(v)))));
-                }
-                return .{ .data = result };
-            }
-        }
-
-        /// Negate every lane.
-        pub inline fn negate(self: Self) Self {
-            return .{ .data = -self.data };
-        }
-
-        // ---------------------------------------------------------------
-        // Conversion
-        // ---------------------------------------------------------------
-
-        /// Convert to a compatible quantity type.  Dimension mismatch is a compile error.
-        /// The scale ratio is computed entirely at comptime; the only runtime cost is
-        /// a SIMD multiply-by-splat (or element-wise cast for cross-numeric-type conversions).
-        pub inline fn to(self: Self, comptime Dest: type) Dest {
-            if (comptime !dims.eql(Dest.dims))
-                @compileError("Dimension mismatch in to: " ++ dims.str() ++ " vs " ++ Dest.dims.str());
-            if (comptime Self == Dest) return self;
-            comptime std.debug.assert(Dest.Len == N);
-
-            const DestT = Dest.ValueType;
-            const ratio = comptime (scales.getFactor(dims) / Dest.scales.getFactor(Dest.dims));
-            const DestVec = @Vector(N, DestT);
-
-            // ── Fast path: same numeric type → pure SIMD ──────────────
-            if (comptime T == DestT) {
-                if (comptime @typeInfo(T) == .float) {
-                    return .{ .data = self.data * @as(DestVec, @splat(@as(T, @floatCast(ratio)))) };
-                }
-                // Integer same-T
-                if (comptime ratio >= 1.0 and @round(ratio) == ratio) {
-                    const mult: T = comptime @intFromFloat(ratio);
-                    return .{ .data = self.data *| @as(Vec, @splat(mult)) };
-                }
-                // Sub-unit ratio: rounded integer divide, element-wise.
-                const d: T = comptime @intFromFloat(1.0 / ratio);
-                var result: DestVec = undefined;
-                inline for (0..N) |i| {
-                    const val = self.data[i];
-                    const half: T = comptime d / 2;
-                    result[i] = if (val >= 0) @divTrunc(val + half, d) else @divTrunc(val - half, d);
-                }
-                return .{ .data = result };
-            }
-
-            // ── Cross-numeric-type: go through f64 element-wise ────────
-            var result: DestVec = undefined;
-            inline for (0..N) |i| {
-                const float_val: f64 = switch (comptime @typeInfo(T)) {
-                    .float => @floatCast(self.data[i]),
-                    .int => @floatFromInt(self.data[i]),
-                    else => unreachable,
-                };
-                const scaled = float_val * ratio;
-                result[i] = switch (comptime @typeInfo(DestT)) {
-                    .float => @floatCast(scaled),
-                    .int => @intFromFloat(@round(scaled)),
-                    else => unreachable,
-                };
-            }
-            return .{ .data = result };
-        }
-
-        // ---------------------------------------------------------------
-        // Comparisons
-        //
-        // Return type:  bool    when N = 1  (Scalar semantics)
-        //               [N]bool when N > 1  (Vector semantics, element-wise)
-        //
-        // Whole-vector "all equal/any differ" → use eqAll / neAll.
-        // Broadcast scalar comparison         → use eqScalar / gtScalar / …
-        // ---------------------------------------------------------------
-
-        const CmpResult = if (N == 1) bool else [N]bool;
-
-        inline fn cmpResult(v: @Vector(N, bool)) CmpResult {
-            return if (comptime N == 1) v[0] else @as([N]bool, v);
-        }
-
-        inline fn resolveScalePair(self: Self, rhs_q: anytype) struct { l: Vec, r: Vec } {
-            const RhsType = @TypeOf(rhs_q);
-            const TargetType = Quantity(T, N, dims.argsOpt(), hlp.finerScales(Self, RhsType).argsOpt());
-            return .{
-                .l = if (comptime Self == TargetType) self.data else self.to(TargetType).data,
-                .r = if (comptime RhsType == TargetType) rhs_q.data else rhs_q.to(TargetType).data,
-            };
-        }
-
-        pub inline fn eq(self: Self, r: anytype) CmpResult {
-            const rhs_q = rhs(r);
-            if (comptime !dims.eql(@TypeOf(rhs_q).dims))
-                @compileError("Dimension mismatch in eq: " ++ dims.str() ++ " vs " ++ @TypeOf(rhs_q).dims.str());
-            const p = resolveScalePair(self, rhs_q);
-            return cmpResult(p.l == p.r);
-        }
-
-        pub inline fn ne(self: Self, r: anytype) CmpResult {
-            const rhs_q = rhs(r);
-            if (comptime !dims.eql(@TypeOf(rhs_q).dims))
-                @compileError("Dimension mismatch in ne.");
-            const p = resolveScalePair(self, rhs_q);
-            return cmpResult(p.l != p.r);
-        }
-
-        pub inline fn gt(self: Self, r: anytype) CmpResult {
-            const rhs_q = rhs(r);
-            if (comptime !dims.eql(@TypeOf(rhs_q).dims))
-                @compileError("Dimension mismatch in gt.");
-            const p = resolveScalePair(self, rhs_q);
-            return cmpResult(p.l > p.r);
-        }
-
-        pub inline fn gte(self: Self, r: anytype) CmpResult {
-            const rhs_q = rhs(r);
-            if (comptime !dims.eql(@TypeOf(rhs_q).dims))
-                @compileError("Dimension mismatch in gte.");
-            const p = resolveScalePair(self, rhs_q);
-            return cmpResult(p.l >= p.r);
-        }
-
-        pub inline fn lt(self: Self, r: anytype) CmpResult {
-            const rhs_q = rhs(r);
-            if (comptime !dims.eql(@TypeOf(rhs_q).dims))
-                @compileError("Dimension mismatch in lt.");
-            const p = resolveScalePair(self, rhs_q);
-            return cmpResult(p.l < p.r);
-        }
-
-        pub inline fn lte(self: Self, r: anytype) CmpResult {
-            const rhs_q = rhs(r);
-            if (comptime !dims.eql(@TypeOf(rhs_q).dims))
-                @compileError("Dimension mismatch in lte.");
-            const p = resolveScalePair(self, rhs_q);
-            return cmpResult(p.l <= p.r);
-        }
-
-        // ---------------------------------------------------------------
-        // Vector whole-quantity comparisons  (N > 1 intended, but work for N=1 too)
-        // ---------------------------------------------------------------
-
-        /// True iff every lane is equal after scale resolution.
-        pub inline fn eqAll(self: Self, other: anytype) bool {
-            if (comptime !dims.eql(@TypeOf(other).dims))
-                @compileError("Dimension mismatch in eqAll.");
-            const p = resolveScalePair(self, other);
-            return @reduce(.And, p.l == p.r);
-        }
-
-        pub inline fn neAll(self: Self, other: anytype) bool {
-            return !self.eqAll(other);
-        }
-
-        // ---------------------------------------------------------------
-        // Vector broadcast-scalar comparisons  (always returns [N]bool)
-        // ---------------------------------------------------------------
-
-        inline fn broadcastScalarForCmp(self: Self, scalar: anytype) struct { l: Vec, r: Vec } {
-            const s = scalarRhs(scalar);
-            const SN = @TypeOf(s);
-            const TargetScalar = Quantity(T, 1, dims.argsOpt(), hlp.finerScales(Self, SN).argsOpt());
-            const TargetSelf = Quantity(T, N, dims.argsOpt(), hlp.finerScales(Self, SN).argsOpt());
-            const s_val: T = if (comptime SN == TargetScalar) s.data[0] else s.to(TargetScalar).data[0];
-            const l: Vec = if (comptime Self == TargetSelf) self.data else self.to(TargetSelf).data;
-            return .{ .l = l, .r = @splat(s_val) };
-        }
-
-        pub inline fn eqScalar(self: Self, scalar: anytype) [N]bool {
-            const p = broadcastScalarForCmp(self, scalar);
-            return @as([N]bool, p.l == p.r);
-        }
-
-        pub inline fn neScalar(self: Self, scalar: anytype) [N]bool {
-            const p = broadcastScalarForCmp(self, scalar);
-            return @as([N]bool, p.l != p.r);
-        }
-
-        pub inline fn gtScalar(self: Self, scalar: anytype) [N]bool {
-            const p = broadcastScalarForCmp(self, scalar);
-            return @as([N]bool, p.l > p.r);
-        }
-
-        pub inline fn gteScalar(self: Self, scalar: anytype) [N]bool {
-            const p = broadcastScalarForCmp(self, scalar);
-            return @as([N]bool, p.l >= p.r);
-        }
-
-        pub inline fn ltScalar(self: Self, scalar: anytype) [N]bool {
-            const p = broadcastScalarForCmp(self, scalar);
-            return @as([N]bool, p.l < p.r);
-        }
-
-        pub inline fn lteScalar(self: Self, scalar: anytype) [N]bool {
-            const p = broadcastScalarForCmp(self, scalar);
-            return @as([N]bool, p.l <= p.r);
-        }
-
-        // ---------------------------------------------------------------
-        // Vector broadcast multiply / divide
-        // (These are explicit aliases for mul/div with an N=1 rhs; kept for
-        //  clarity and backward-compat with the old Vector API.)
-        // ---------------------------------------------------------------
-
-        pub inline fn mulScalar(self: Self, scalar: anytype) Quantity(
-            T,
-            N,
-            dims.add(ScalarRhsT(@TypeOf(scalar)).dims).argsOpt(),
-            hlp.finerScales(Self, ScalarRhsT(@TypeOf(scalar))).argsOpt(),
-        ) {
-            return self.mul(scalar);
-        }
-
-        pub inline fn divScalar(self: Self, scalar: anytype) Quantity(
-            T,
-            N,
-            dims.sub(ScalarRhsT(@TypeOf(scalar)).dims).argsOpt(),
-            hlp.finerScales(Self, ScalarRhsT(@TypeOf(scalar))).argsOpt(),
-        ) {
-            return self.div(scalar);
-        }
-
-        // ---------------------------------------------------------------
-        // Vector geometric operations
-        // ---------------------------------------------------------------
-
-        /// Dot product — sum of element-wise products; returns a Scalar.
-        pub inline fn dot(self: Self, other: anytype) Quantity(
-            T,
-            1,
-            dims.add(@TypeOf(other).dims).argsOpt(),
-            hlp.finerScales(Self, @TypeOf(other)).argsOpt(),
-        ) {
-            const Tr = @TypeOf(other);
-            const SelfNorm = Quantity(T, N, dims.argsOpt(), hlp.finerScales(Self, Tr).argsOpt());
-            const OtherNorm = Quantity(T, N, Tr.dims.argsOpt(), hlp.finerScales(Self, Tr).argsOpt());
-            const l: Vec = if (comptime Self == SelfNorm) self.data else self.to(SelfNorm).data;
-            const r2: Vec = if (comptime Tr == OtherNorm) other.data else other.to(OtherNorm).data;
-            return .{ .data = .{@reduce(.Add, l * r2)} };
-        }
-
-        /// 3D cross product. Requires N = 3.
-        pub inline fn cross(self: Self, other: anytype) Quantity(
-            T,
-            3,
-            dims.add(@TypeOf(other).dims).argsOpt(),
-            hlp.finerScales(Self, @TypeOf(other)).argsOpt(),
-        ) {
-            comptime if (N != 3) @compileError("cross() requires len=3.");
-            const a = self.data;
-            const b = other.data;
-            return .{ .data = .{
-                a[1] * b[2] - a[2] * b[1],
-                a[2] * b[0] - a[0] * b[2],
-                a[0] * b[1] - a[1] * b[0],
-            } };
-        }
-
-        /// Sum of squared components.  Cheaper than length(); use for comparisons.
-        pub inline fn lengthSqr(self: Self) T {
-            return @reduce(.Add, self.data * self.data);
-        }
-
-        /// Euclidean length.  Float types use SIMD @reduce → @sqrt.
-        /// Integer types use integer sqrt (truncated).
-        pub inline fn length(self: Self) T {
-            const sq = self.lengthSqr();
-            if (comptime @typeInfo(T) == .int) {
-                const UnsignedT = @Int(.unsigned, @typeInfo(T).int.bits);
-                return @as(T, @intCast(std.math.sqrt(@as(UnsignedT, @intCast(sq)))));
-            }
-            return @sqrt(sq);
-        }
-
-        /// Product of all components.  Result dimension is (original dim × N).
-        pub inline fn product(self: Self) Quantity(T, 1, dims.scale(N).argsOpt(), scales.argsOpt()) {
-            return .{ .data = .{@reduce(.Mul, self.data)} };
-        }
-
-        // ---------------------------------------------------------------
-        // Formatting  (unchanged from old Scalar / Vector)
-        // ---------------------------------------------------------------
-
-        pub fn formatNumber(
-            self: Self,
-            writer: *std.Io.Writer,
-            options: std.fmt.Number,
-        ) !void {
-            if (comptime N == 1) {
-                // Scalar-style: just print the value + units
-                switch (@typeInfo(T)) {
-                    .float, .comptime_float => try writer.printFloat(self.data[0], options),
-                    .int, .comptime_int => try writer.printInt(self.data[0], 10, .lower, .{
-                        .width = options.width,
-                        .alignment = options.alignment,
-                        .fill = options.fill,
-                        .precision = options.precision,
-                    }),
-                    else => unreachable,
-                }
-            } else {
-                // Vector-style: (v0, v1, …) + units
-                try writer.writeAll("(");
-                inline for (0..N) |i| {
-                    if (i > 0) try writer.writeAll(", ");
-                    switch (@typeInfo(T)) {
-                        .float, .comptime_float => try writer.printFloat(self.data[i], options),
-                        .int, .comptime_int => try writer.printInt(self.data[i], 10, .lower, .{
-                            .width = options.width,
-                            .alignment = options.alignment,
-                            .fill = options.fill,
-                            .precision = options.precision,
-                        }),
-                        else => unreachable,
-                    }
-                }
-                try writer.writeAll(")");
-            }
-
-            var first = true;
-            inline for (std.enums.values(Dimension)) |bu| {
-                const v = dims.get(bu);
-                if (comptime v == 0) continue;
-                if (!first) try writer.writeAll(".");
-                first = false;
-
-                const uscale = scales.get(bu);
-                if (bu == .T and (uscale == .min or uscale == .hour or uscale == .year))
-                    try writer.print("{s}", .{uscale.str()})
-                else
-                    try writer.print("{s}{s}", .{ uscale.str(), bu.unit() });
-
-                if (v != 1) try hlp.printSuperscript(writer, v);
-            }
-        }
-    };
-}
-
-fn Scalar(comptime T: type, comptime d: Dimensions.ArgOpts, comptime s: Scales.ArgOpts) type {
-    return Quantity(T, 1, d, s);
-}
-
-test "Generate quantity" {
-    const Meter = Scalar(i128, .{ .L = 1 }, .{ .L = @enumFromInt(-3) });
-    const Second = Scalar(f32, .{ .T = 1 }, .{ .T = .n });
-
-    const distance = Meter.splat(10);
-    const time = Second.splat(2);
-
-    try std.testing.expectEqual(10, distance.value());
-    try std.testing.expectEqual(2, time.value());
-}

src/Scalar.zig

@@ -1,815 +0,0 @@
-const std = @import("std");
-const hlp = @import("helper.zig");
-
-const Vector = @import("Vector.zig").Vector;
-const Scales = @import("Scales.zig");
-const UnitScale = Scales.UnitScale;
-const Dimensions = @import("Dimensions.zig");
-const Dimension = Dimensions.Dimension;
-
-/// A dimensioned scalar value. `T` is the numeric type, `d` the dimension exponents, `s` the SI scales.
-/// All dimension and unit tracking is resolved at comptime — zero runtime overhead.
-pub fn Scalar(comptime T: type, comptime d_opt: Dimensions.ArgOpts, comptime s_opt: Scales.ArgOpts) type {
-    @setEvalBranchQuota(10_000_000);
-    return struct {
-        value: T,
-
-        const Self = @This();
-
-        /// Type of Vector(3, Self)
-        pub const Vec3: type = Vector(3, Self);
-
-        /// Type of underline value, mostly use for Vector
-        pub const ValueType: type = T;
-        pub const dims: Dimensions = Dimensions.init(d_opt);
-        pub const scales = Scales.init(s_opt);
-
-        // ---------------------------------------------------------------
-        // Internal: resolved-rhs shorthands
-        // ---------------------------------------------------------------
-
-        /// Scalar type that `rhs` normalises to (bare numbers → dimensionless).
-        inline fn RhsT(comptime Rhs: type) type {
-            return hlp.rhsScalarType(T, Rhs);
-        }
-
-        /// Normalise `rhs` (bare number or Scalar) into a proper Scalar value.
-        inline fn rhs(r: anytype) RhsT(@TypeOf(r)) {
-            return hlp.toRhsScalar(T, r);
-        }
-
-        // ---------------------------------------------------------------
-        // Arithmetic
-        // ---------------------------------------------------------------
-
-        /// Add two quantities. Dimensions must match — compile error otherwise.
-        /// Scales are auto-resolved to the finer of the two.
-        /// `rhs` may be a Scalar, `T`, `comptime_int`, or `comptime_float`
-        /// (bare numbers are treated as dimensionless).
-        pub inline fn add(self: Self, r: anytype) Scalar(
-            T,
-            dims.argsOpt(),
-            hlp.finerScales(Self, RhsT(@TypeOf(r))).argsOpt(),
-        ) {
-            const rhs_s = rhs(r);
-            const RhsType = @TypeOf(rhs_s);
-            if (comptime !dims.eql(RhsType.dims))
-                @compileError("Dimension mismatch in add: " ++ dims.str() ++ " vs " ++ RhsType.dims.str());
-            if (comptime RhsType == Self)
-                return .{ .value = self.value + rhs_s.value };
-
-            const TargetType = Scalar(T, dims.argsOpt(), hlp.finerScales(Self, RhsType).argsOpt());
-            const lhs_val = if (comptime Self == TargetType) self.value else self.to(TargetType).value;
-            const rhs_val = if (comptime RhsType == TargetType) rhs_s.value else rhs_s.to(TargetType).value;
-            return .{ .value = if (comptime hlp.isInt(T)) lhs_val +| rhs_val else lhs_val + rhs_val };
-        }
-
-        /// Subtract two quantities. Dimensions must match — compile error otherwise.
-        /// Scales are auto-resolved to the finer of the two.
-        /// `rhs` may be a Scalar, `T`, `comptime_int`, or `comptime_float`.
-        pub inline fn sub(self: Self, r: anytype) Scalar(
-            T,
-            dims.argsOpt(),
-            hlp.finerScales(Self, RhsT(@TypeOf(r))).argsOpt(),
-        ) {
-            const rhs_s = rhs(r);
-            const RhsType = @TypeOf(rhs_s);
-            if (comptime !dims.eql(RhsType.dims))
-                @compileError("Dimension mismatch in sub: " ++ dims.str() ++ " vs " ++ RhsType.dims.str());
-            if (comptime RhsType == Self)
-                return .{ .value = self.value - rhs_s.value };
-
-            const TargetType = Scalar(T, dims.argsOpt(), hlp.finerScales(Self, RhsType).argsOpt());
-            const lhs_val = if (comptime Self == TargetType) self.value else self.to(TargetType).value;
-            const rhs_val = if (comptime RhsType == TargetType) rhs_s.value else rhs_s.to(TargetType).value;
-            return .{ .value = if (comptime hlp.isInt(T)) lhs_val -| rhs_val else lhs_val - rhs_val };
-        }
-
-        /// Multiply two quantities. Dimension exponents are summed: `L¹ * T⁻¹ → L¹T⁻¹`.
-        /// `rhs` may be a Scalar, `T`, `comptime_int`, or `comptime_float`
-        /// (bare numbers are treated as dimensionless — dimensions pass through unchanged).
-        pub inline fn mul(self: Self, r: anytype) Scalar(
-            T,
-            dims.add(RhsT(@TypeOf(r)).dims).argsOpt(),
-            hlp.finerScales(Self, RhsT(@TypeOf(r))).argsOpt(),
-        ) {
-            const rhs_s = rhs(r);
-            const RhsType = @TypeOf(rhs_s);
-            const SelfNorm = Scalar(T, dims.argsOpt(), hlp.finerScales(Self, RhsType).argsOpt());
-            const RhsNorm = Scalar(T, RhsType.dims.argsOpt(), hlp.finerScales(Self, RhsType).argsOpt());
-            if (comptime Self == SelfNorm and RhsType == RhsNorm)
-                return .{ .value = self.value * rhs_s.value };
-
-            const lhs_val = if (comptime Self == SelfNorm) self.value else self.to(SelfNorm).value;
-            const rhs_val = if (comptime RhsType == RhsNorm) rhs_s.value else rhs_s.to(RhsNorm).value;
-            return .{ .value = if (comptime hlp.isInt(T)) lhs_val *| rhs_val else lhs_val * rhs_val };
-        }
-
-        /// Divide two quantities. Dimension exponents are subtracted: `L¹ / T¹ → L¹T⁻¹`.
-        /// Integer types use truncating division.
-        /// `rhs` may be a Scalar, `T`, `comptime_int`, or `comptime_float`.
-        pub inline fn div(self: Self, r: anytype) Scalar(
-            T,
-            dims.sub(RhsT(@TypeOf(r)).dims).argsOpt(),
-            hlp.finerScales(Self, RhsT(@TypeOf(r))).argsOpt(),
-        ) {
-            const rhs_s = rhs(r);
-            const RhsType = @TypeOf(rhs_s);
-            const SelfNorm = Scalar(T, dims.argsOpt(), hlp.finerScales(Self, RhsType).argsOpt());
-            const RhsNorm = Scalar(T, RhsType.dims.argsOpt(), hlp.finerScales(Self, RhsType).argsOpt());
-            const lhs_val = if (comptime Self == SelfNorm) self.value else self.to(SelfNorm).value;
-            const rhs_val = if (comptime RhsType == RhsNorm) rhs_s.value else rhs_s.to(RhsNorm).value;
-            if (comptime hlp.isInt(T)) {
-                return .{ .value = @divTrunc(lhs_val, rhs_val) };
-            } else {
-                return .{ .value = lhs_val / rhs_val };
-            }
-        }
-
-        // ---------------------------------------------------------------
-        // Unary
-        // ---------------------------------------------------------------
-
-        /// Returns the absolute value of the quantity.
-        /// Dimensions and scales remain entirely unchanged.
-        pub inline fn abs(self: Self) Self {
-            if (comptime @typeInfo(T) == .int)
-                return .{ .value = @intCast(@abs(self.value)) }
-            else
-                return .{ .value = @abs(self.value) };
-        }
-
-        /// Raises the quantity to a compile-time integer exponent.
-        /// Dimension exponents are multiplied by the exponent: `(L²)³ → L⁶`.
-        pub inline fn pow(self: Self, comptime exp: comptime_int) Scalar(
-            T,
-            dims.scale(exp).argsOpt(),
-            scales.argsOpt(),
-        ) {
-            if (comptime hlp.isInt(T))
-                return .{ .value = std.math.powi(T, self.value, exp) catch std.math.maxInt(T) }
-            else
-                return .{ .value = std.math.pow(T, self.value, @as(T, @floatFromInt(exp))) };
-        }
-
-        pub inline fn sqrt(self: Self) Scalar(
-            T,
-            dims.div(2).argsOpt(),
-            scales.argsOpt(),
-        ) {
-            if (comptime !dims.isSquare()) // Check if all exponents are divisible by 2
-                @compileError("Cannot take sqrt of " ++ dims.str() ++ ": exponents must be even.");
-            if (self.value < 0) return .{ .value = 0 };
-
-            if (comptime hlp.isInt(T)) {
-                const UnsignedT = @Int(.unsigned, @typeInfo(T).int.bits);
-                const u_len_sq = @as(UnsignedT, @intCast(self.value));
-                return .{ .value = @as(T, @intCast(std.math.sqrt(u_len_sq))) };
-            } else {
-                return .{ .value = @sqrt(self.value) };
-            }
-        }
-
-        // ---------------------------------------------------------------
-        // Conversion
-        // ---------------------------------------------------------------
-
-        /// Convert to a compatible unit type. The scale ratio is computed at comptime.
-        /// Compile error if dimensions don't match.
-        pub inline fn to(self: Self, comptime Dest: type) Dest {
-            if (comptime !dims.eql(Dest.dims))
-                @compileError("Dimension mismatch in to: " ++ dims.str() ++ " vs " ++ Dest.dims.str());
-            if (comptime @TypeOf(self) == Dest)
-                return self;
-
-            const DestT = Dest.ValueType;
-            const ratio = comptime (scales.getFactor(dims) / Dest.scales.getFactor(Dest.dims));
-
-            // Fast-path: Native pure-integer exact conversions
-            if (comptime @typeInfo(T) == .int and @typeInfo(DestT) == .int) {
-                if (comptime ratio >= 1.0 and @round(ratio) == ratio) {
-                    const mult: DestT = comptime @intFromFloat(ratio);
-                    return .{ .value = @as(DestT, @intCast(self.value)) * mult };
-                } else if (comptime ratio < 1.0 and @round(1.0 / ratio) == 1.0 / ratio) {
-                    const d: DestT = comptime @intFromFloat(1.0 / ratio);
-                    const val = @as(DestT, @intCast(self.value));
-                    const half = comptime d / 2;
-                    const rounded = if (val >= 0) @divTrunc(val + half, d) else @divTrunc(val - half, d);
-                    return .{ .value = rounded };
-                }
-            }
-
-            // Fallback preserving native Float types (e.g., f128 shouldn't downcast to f64)
-            if (comptime @typeInfo(DestT) == .float) {
-                const val_f = switch (@typeInfo(T)) {
-                    inline .int => @as(DestT, @floatFromInt(self.value)),
-                    inline .float => @as(DestT, @floatCast(self.value)),
-                    else => unreachable,
-                };
-                return .{ .value = val_f * @as(DestT, @floatCast(ratio)) };
-            } else {
-                const val_f = switch (@typeInfo(T)) {
-                    inline .int => @as(f64, @floatFromInt(self.value)),
-                    inline .float => @as(f64, @floatCast(self.value)),
-                    else => unreachable,
-                };
-                return .{ .value = @intFromFloat(@round(val_f * ratio)) };
-            }
-        }
-
-        // ---------------------------------------------------------------
-        // Comparisons
-        // ---------------------------------------------------------------
-
-        /// Compares two Scalar for exact equality.
-        /// Dimensions must match — compile error otherwise. Scales are auto-resolved.
-        /// `rhs` may be a Scalar, `T`, `comptime_int`, or `comptime_float`.
-        pub inline fn eq(self: Self, r: anytype) bool {
-            const rhs_s = rhs(r);
-            const RhsType = @TypeOf(rhs_s);
-            if (comptime !dims.eql(RhsType.dims))
-                @compileError("Dimension mismatch in eq: " ++ dims.str() ++ " vs " ++ RhsType.dims.str());
-            if (comptime RhsType == Self)
-                return self.value == rhs_s.value;
-
-            const TargetType = Scalar(T, dims.argsOpt(), hlp.finerScales(Self, RhsType).argsOpt());
-            const lhs_val = if (comptime Self == TargetType) self.value else self.to(TargetType).value;
-            const rhs_val = if (comptime RhsType == TargetType) rhs_s.value else rhs_s.to(TargetType).value;
-            return lhs_val == rhs_val;
-        }
-
-        /// Compares two quantities for inequality.
-        /// Dimensions must match — compile error otherwise. Scales are auto-resolved.
-        /// `rhs` may be a Scalar, `T`, `comptime_int`, or `comptime_float`.
-        pub inline fn ne(self: Self, r: anytype) bool {
-            const rhs_s = rhs(r);
-            const RhsType = @TypeOf(rhs_s);
-            if (comptime !dims.eql(RhsType.dims))
-                @compileError("Dimension mismatch in ne: " ++ dims.str() ++ " vs " ++ RhsType.dims.str());
-            if (comptime RhsType == Self)
-                return self.value != rhs_s.value;
-
-            const TargetType = Scalar(T, dims.argsOpt(), hlp.finerScales(Self, RhsType).argsOpt());
-            const lhs_val = if (comptime Self == TargetType) self.value else self.to(TargetType).value;
-            const rhs_val = if (comptime RhsType == TargetType) rhs_s.value else rhs_s.to(TargetType).value;
-            return lhs_val != rhs_val;
-        }
-
-        /// Returns true if this quantity is strictly greater than the right-hand side.
-        /// Dimensions must match — compile error otherwise. Scales are auto-resolved.
-        /// `rhs` may be a Scalar, `T`, `comptime_int`, or `comptime_float`.
-        pub inline fn gt(self: Self, r: anytype) bool {
-            const rhs_s = rhs(r);
-            const RhsType = @TypeOf(rhs_s);
-            if (comptime !dims.eql(RhsType.dims))
-                @compileError("Dimension mismatch in gt: " ++ dims.str() ++ " vs " ++ RhsType.dims.str());
-            if (comptime RhsType == Self)
-                return self.value > rhs_s.value;
-
-            const TargetType = Scalar(T, dims.argsOpt(), hlp.finerScales(Self, RhsType).argsOpt());
-            const lhs_val = if (comptime Self == TargetType) self.value else self.to(TargetType).value;
-            const rhs_val = if (comptime RhsType == TargetType) rhs_s.value else rhs_s.to(TargetType).value;
-            return lhs_val > rhs_val;
-        }
-
-        /// Returns true if this quantity is greater than or equal to the right-hand side.
-        /// Dimensions must match — compile error otherwise. Scales are auto-resolved.
-        /// `rhs` may be a Scalar, `T`, `comptime_int`, or `comptime_float`.
-        pub inline fn gte(self: Self, r: anytype) bool {
-            const rhs_s = rhs(r);
-            const RhsType = @TypeOf(rhs_s);
-            if (comptime !dims.eql(RhsType.dims))
-                @compileError("Dimension mismatch in gte: " ++ dims.str() ++ " vs " ++ RhsType.dims.str());
-            if (comptime RhsType == Self)
-                return self.value >= rhs_s.value;
-
-            const TargetType = Scalar(T, dims.argsOpt(), hlp.finerScales(Self, RhsType).argsOpt());
-            const lhs_val = if (comptime Self == TargetType) self.value else self.to(TargetType).value;
-            const rhs_val = if (comptime RhsType == TargetType) rhs_s.value else rhs_s.to(TargetType).value;
-            return lhs_val >= rhs_val;
-        }
-
-        /// Returns true if this quantity is strictly less than the right-hand side.
-        /// Dimensions must match — compile error otherwise. Scales are auto-resolved.
-        /// `rhs` may be a Scalar, `T`, `comptime_int`, or `comptime_float`.
-        pub inline fn lt(self: Self, r: anytype) bool {
-            const rhs_s = rhs(r);
-            const RhsType = @TypeOf(rhs_s);
-            if (comptime !dims.eql(RhsType.dims))
-                @compileError("Dimension mismatch in lt: " ++ dims.str() ++ " vs " ++ RhsType.dims.str());
-            if (comptime RhsType == Self)
-                return self.value < rhs_s.value;
-
-            const TargetType = Scalar(T, dims.argsOpt(), hlp.finerScales(Self, RhsType).argsOpt());
-            const lhs_val = if (comptime Self == TargetType) self.value else self.to(TargetType).value;
-            const rhs_val = if (comptime RhsType == TargetType) rhs_s.value else rhs_s.to(TargetType).value;
-            return lhs_val < rhs_val;
-        }
-
-        /// Returns true if this quantity is less than or equal to the right-hand side.
-        /// Dimensions must match — compile error otherwise. Scales are auto-resolved.
-        /// `rhs` may be a Scalar, `T`, `comptime_int`, or `comptime_float`.
-        pub inline fn lte(self: Self, r: anytype) bool {
-            const rhs_s = rhs(r);
-            const RhsType = @TypeOf(rhs_s);
-            if (comptime !dims.eql(RhsType.dims))
-                @compileError("Dimension mismatch in lte: " ++ dims.str() ++ " vs " ++ RhsType.dims.str());
-            if (comptime RhsType == Self)
-                return self.value <= rhs_s.value;
-
-            const TargetType = Scalar(T, dims.argsOpt(), hlp.finerScales(Self, RhsType).argsOpt());
-            const lhs_val = if (comptime Self == TargetType) self.value else self.to(TargetType).value;
-            const rhs_val = if (comptime RhsType == TargetType) rhs_s.value else rhs_s.to(TargetType).value;
-            return lhs_val <= rhs_val;
-        }
-
-        // ---------------------------------------------------------------
-        // Vector helpers
-        // ---------------------------------------------------------------
-
-        /// Return a `Vector(len, Self)` type.
-        pub fn Vec(_: Self, comptime len: comptime_int) type {
-            return Vector(len, Self);
-        }
-
-        /// Return a `Vector(len, Self)` with all components set to this value.
-        pub fn vec(self: Self, comptime len: comptime_int) Vector(len, Self) {
-            return Vector(len, Self).initDefault(self.value);
-        }
-
-        /// Shorthand for `Vec(3)` — wrap this value into a 3-component vector.
-        pub fn vec3(self: Self) Vec3 {
-            return Vec3.initDefault(self.value);
-        }
-
-        // ---------------------------------------------------------------
-        // Formatting
-        // ---------------------------------------------------------------
-
-        pub fn formatNumber(
-            self: Self,
-            writer: *std.Io.Writer,
-            options: std.fmt.Number,
-        ) !void {
-            switch (@typeInfo(T)) {
-                .float, .comptime_float => try writer.printFloat(self.value, options),
-                .int, .comptime_int => try writer.printInt(self.value, 10, .lower, .{
-                    .width = options.width,
-                    .alignment = options.alignment,
-                    .fill = options.fill,
-                    .precision = options.precision,
-                }),
-                else => unreachable,
-            }
-            var first = true;
-            inline for (std.enums.values(Dimension)) |bu| {
-                const v = dims.get(bu);
-                if (comptime v == 0) continue;
-                if (!first)
-                    try writer.writeAll(".");
-
-                first = false;
-
-                const uscale = scales.get(bu);
-                if (bu == .T and (uscale == .min or uscale == .hour or uscale == .year))
-                    try writer.print("{s}", .{uscale.str()})
-                else
-                    try writer.print("{s}{s}", .{ uscale.str(), bu.unit() });
-
-                if (v != 1)
-                    try hlp.printSuperscript(writer, v);
-            }
-        }
-    };
-}
-
-test "Generate quantity" {
-    const Meter = Scalar(i128, .{ .L = 1 }, .{ .L = @enumFromInt(-3) });
-    const Second = Scalar(f32, .{ .T = 1 }, .{ .T = .n });
-
-    const distance = Meter{ .value = 10 };
-    const time = Second{ .value = 2 };
-
-    try std.testing.expectEqual(10, distance.value);
-    try std.testing.expectEqual(2, time.value);
-}
-
-test "Comparisons (eq, ne, gt, gte, lt, lte)" {
-    const Meter = Scalar(i128, .{ .L = 1 }, .{});
-    const KiloMeter = Scalar(i128, .{ .L = 1 }, .{ .L = .k });
-
-    const m1000 = Meter{ .value = 1000 };
-    const km1 = KiloMeter{ .value = 1 };
-    const km2 = KiloMeter{ .value = 2 };
-
-    // Equal / Not Equal
-    try std.testing.expect(m1000.eq(km1));
-    try std.testing.expect(km1.eq(m1000));
-    try std.testing.expect(km2.ne(m1000));
-
-    // Greater Than / Greater Than or Equal
-    try std.testing.expect(km2.gt(m1000));
-    try std.testing.expect(km2.gt(km1));
-    try std.testing.expect(km1.gte(m1000));
-    try std.testing.expect(km2.gte(m1000));
-
-    // Less Than / Less Than or Equal
-    try std.testing.expect(m1000.lt(km2));
-    try std.testing.expect(km1.lt(km2));
-    try std.testing.expect(km1.lte(m1000));
-    try std.testing.expect(m1000.lte(km2));
-}
-
-test "Add" {
-    const Meter = Scalar(i128, .{ .L = 1 }, .{});
-
-    const distance = Meter{ .value = 10 };
-    const distance2 = Meter{ .value = 20 };
-
-    const added = distance.add(distance2);
-    try std.testing.expectEqual(30, added.value);
-    try std.testing.expectEqual(1, @TypeOf(added).dims.get(.L));
-
-    const KiloMeter = Scalar(i128, .{ .L = 1 }, .{ .L = .k });
-    const distance3 = KiloMeter{ .value = 2 };
-    const added2 = distance.add(distance3);
-    try std.testing.expectEqual(2010, added2.value);
-    try std.testing.expectEqual(1, @TypeOf(added2).dims.get(.L));
-
-    const added3 = distance3.add(distance).to(KiloMeter);
-    try std.testing.expectEqual(2, added3.value);
-    try std.testing.expectEqual(1, @TypeOf(added3).dims.get(.L));
-
-    const KiloMeter_f = Scalar(f64, .{ .L = 1 }, .{ .L = .k });
-    const distance4 = KiloMeter_f{ .value = 2 };
-    const added4 = distance4.add(distance).to(KiloMeter_f);
-    try std.testing.expectApproxEqAbs(2.01, added4.value, 0.000001);
-    try std.testing.expectEqual(1, @TypeOf(added4).dims.get(.L));
-}
-
-test "Sub" {
-    const Meter = Scalar(i128, .{ .L = 1 }, .{});
-    const KiloMeter_f = Scalar(f64, .{ .L = 1 }, .{ .L = .k });
-
-    const a = Meter{ .value = 500 };
-    const b = Meter{ .value = 200 };
-    const diff = a.sub(b);
-    try std.testing.expectEqual(300, diff.value);
-    const diff2 = b.sub(a);
-    try std.testing.expectEqual(-300, diff2.value);
-
-    const km_f = KiloMeter_f{ .value = 2.5 };
-    const m_f = Meter{ .value = 500 };
-    const diff3 = km_f.sub(m_f);
-    try std.testing.expectApproxEqAbs(2000, diff3.value, 1e-4);
-}
-
-test "MulBy" {
-    const Meter = Scalar(i128, .{ .L = 1 }, .{});
-    const Second = Scalar(f32, .{ .T = 1 }, .{});
-
-    const d = Meter{ .value = 3.0 };
-    const t = Second{ .value = 4.0 };
-
-    const area_time = d.mul(t);
-    try std.testing.expectEqual(12, area_time.value);
-    try std.testing.expectEqual(1, @TypeOf(area_time).dims.get(.L));
-    try std.testing.expectEqual(1, @TypeOf(area_time).dims.get(.T));
-
-    const d2 = Meter{ .value = 5.0 };
-    const area = d.mul(d2);
-    try std.testing.expectEqual(15, area.value);
-    try std.testing.expectEqual(2, @TypeOf(area).dims.get(.L));
-    try std.testing.expectEqual(0, @TypeOf(area).dims.get(.T));
-}
-
-test "MulBy with scale" {
-    const KiloMeter = Scalar(f32, .{ .L = 1 }, .{ .L = .k });
-    const KiloGram = Scalar(f32, .{ .M = 1 }, .{ .M = .k });
-
-    const dist = KiloMeter{ .value = 2.0 };
-    const mass = KiloGram{ .value = 3.0 };
-    const prod = dist.mul(mass);
-    try std.testing.expectEqual(1, @TypeOf(prod).dims.get(.L));
-    try std.testing.expectEqual(1, @TypeOf(prod).dims.get(.M));
-}
-
-test "MulBy with type change" {
-    const Meter = Scalar(i128, .{ .L = 1 }, .{ .L = .k });
-    const Second = Scalar(f64, .{ .T = 1 }, .{});
-    const KmSec = Scalar(i64, .{ .L = 1, .T = 1 }, .{ .L = .k });
-    const KmSec_f = Scalar(f32, .{ .L = 1, .T = 1 }, .{ .L = .k });
-
-    const d = Meter{ .value = 3.0 };
-    const t = Second{ .value = 4.0 };
-
-    const area_time = d.mul(t).to(KmSec);
-    const area_time_f = d.mul(t).to(KmSec_f);
-    try std.testing.expectEqual(12, area_time.value);
-    try std.testing.expectApproxEqAbs(12, area_time_f.value, 0.0001);
-    try std.testing.expectEqual(1, @TypeOf(area_time).dims.get(.L));
-    try std.testing.expectEqual(1, @TypeOf(area_time).dims.get(.T));
-}
-
-test "MulBy small" {
-    const Meter = Scalar(i128, .{ .L = 1 }, .{ .L = .n });
-    const Second = Scalar(f32, .{ .T = 1 }, .{});
-
-    const d = Meter{ .value = 3.0 };
-    const t = Second{ .value = 4.0 };
-
-    const area_time = d.mul(t);
-    try std.testing.expectEqual(12, area_time.value);
-    try std.testing.expectEqual(1, @TypeOf(area_time).dims.get(.L));
-    try std.testing.expectEqual(1, @TypeOf(area_time).dims.get(.T));
-}
-
-test "MulBy dimensionless" {
-    const DimLess = Scalar(i128, .{}, .{});
-    const Meter = Scalar(i128, .{ .L = 1 }, .{});
-
-    const d = Meter{ .value = 7 };
-    const scaled = d.mul(DimLess{ .value = 3 });
-    try std.testing.expectEqual(21, scaled.value);
-    try std.testing.expectEqual(1, @TypeOf(scaled).dims.get(.L));
-}
-
-test "Sqrt" {
-    const MeterSquare = Scalar(i128, .{ .L = 2 }, .{});
-
-    var d = MeterSquare{ .value = 9 };
-    var scaled = d.sqrt();
-    try std.testing.expectEqual(3, scaled.value);
-    try std.testing.expectEqual(1, @TypeOf(scaled).dims.get(.L));
-
-    d = MeterSquare{ .value = -5 };
-    scaled = d.sqrt();
-    try std.testing.expectEqual(0, scaled.value);
-    try std.testing.expectEqual(1, @TypeOf(scaled).dims.get(.L));
-
-    const MeterSquare_f = Scalar(f64, .{ .L = 2 }, .{});
-    const d2 = MeterSquare_f{ .value = 20 };
-    const scaled2 = d2.sqrt();
-    try std.testing.expectApproxEqAbs(4.472135955, scaled2.value, 1e-4);
-    try std.testing.expectEqual(1, @TypeOf(scaled2).dims.get(.L));
-}
-
-test "Chained: velocity and acceleration" {
-    const Meter = Scalar(i128, .{ .L = 1 }, .{});
-    const Second = Scalar(f32, .{ .T = 1 }, .{});
-
-    const dist = Meter{ .value = 100.0 };
-    const t1 = Second{ .value = 5.0 };
-    const velocity = dist.div(t1);
-    try std.testing.expectEqual(20, velocity.value);
-    try std.testing.expectEqual(1, @TypeOf(velocity).dims.get(.L));
-    try std.testing.expectEqual(-1, @TypeOf(velocity).dims.get(.T));
-
-    const t2 = Second{ .value = 4.0 };
-    const accel = velocity.div(t2);
-    try std.testing.expectEqual(5, accel.value);
-    try std.testing.expectEqual(1, @TypeOf(accel).dims.get(.L));
-    try std.testing.expectEqual(-2, @TypeOf(accel).dims.get(.T));
-}
-
-test "DivBy integer exact" {
-    const Meter = Scalar(i128, .{ .L = 1 }, .{});
-    const Second = Scalar(f32, .{ .T = 1 }, .{});
-
-    const dist = Meter{ .value = 120 };
-    const time = Second{ .value = 4 };
-    const vel = dist.div(time);
-
-    try std.testing.expectEqual(30, vel.value);
-    try std.testing.expectEqual(1, @TypeOf(vel).dims.get(.L));
-    try std.testing.expectEqual(-1, @TypeOf(vel).dims.get(.T));
-}
-
-test "Finer scales skip dim 0" {
-    const Dimless = Scalar(i128, .{}, .{});
-    const KiloMetre = Scalar(i128, .{ .L = 1 }, .{ .L = .k });
-
-    const r = Dimless{ .value = 30 };
-    const time = KiloMetre{ .value = 4 };
-    const vel = r.mul(time);
-
-    try std.testing.expectEqual(120, vel.value);
-    try std.testing.expectEqual(Scales.UnitScale.k, @TypeOf(vel).scales.get(.L));
-}
-
-test "Conversion chain: km -> m -> cm" {
-    const KiloMeter = Scalar(i128, .{ .L = 1 }, .{ .L = .k });
-    const Meter = Scalar(i128, .{ .L = 1 }, .{});
-    const CentiMeter = Scalar(i128, .{ .L = 1 }, .{ .L = .c });
-
-    const km = KiloMeter{ .value = 15 };
-    const m = km.to(Meter);
-    const cm = m.to(CentiMeter);
-
-    try std.testing.expectEqual(15_000, m.value);
-    try std.testing.expectEqual(1_500_000, cm.value);
-}
-
-test "Conversion: hours -> minutes -> seconds" {
-    const Hour = Scalar(i128, .{ .T = 1 }, .{ .T = .hour });
-    const Minute = Scalar(i128, .{ .T = 1 }, .{ .T = .min });
-    const Second = Scalar(i128, .{ .T = 1 }, .{});
-
-    const h = Hour{ .value = 1.0 };
-    const min = h.to(Minute);
-    const sec = min.to(Second);
-
-    try std.testing.expectEqual(60, min.value);
-    try std.testing.expectEqual(3600, sec.value);
-}
-
-test "Negative values" {
-    const Meter = Scalar(i128, .{ .L = 1 }, .{});
-
-    const a = Meter{ .value = 5 };
-    const b = Meter{ .value = 20 };
-    const diff = a.sub(b);
-    try std.testing.expectEqual(-15, diff.value);
-}
-
-test "Format Scalar" {
-    const MeterPerSecondSq = Scalar(f32, .{ .L = 1, .T = -2 }, .{ .T = .n });
-    const KgMeterPerSecond = Scalar(f32, .{ .M = 1, .L = 1, .T = -1 }, .{ .M = .k });
-    const Meter = Scalar(f32, .{ .L = 1 }, .{});
-
-    const m = Meter{ .value = 1.23456 };
-    const accel = MeterPerSecondSq{ .value = 9.81 };
-    const momentum = KgMeterPerSecond{ .value = 42.0 };
-
-    var buf: [64]u8 = undefined;
-    var res = try std.fmt.bufPrint(&buf, "{d:.2}", .{m});
-    try std.testing.expectEqualStrings("1.23m", res);
-
-    res = try std.fmt.bufPrint(&buf, "{d}", .{accel});
-    try std.testing.expectEqualStrings("9.81m.ns⁻²", res);
-
-    res = try std.fmt.bufPrint(&buf, "{d}", .{momentum});
-    try std.testing.expectEqualStrings("42m.kg.s⁻¹", res);
-
-    res = try std.fmt.bufPrint(&buf, "{d:_>10.1}", .{m});
-    try std.testing.expectEqualStrings("_______1.2m", res);
-}
-
-test "Abs" {
-    const Meter = Scalar(i128, .{ .L = 1 }, .{});
-    const m1 = Meter{ .value = -50 };
-    const m2 = m1.abs();
-
-    try std.testing.expectEqual(50, m2.value);
-    try std.testing.expectEqual(1, @TypeOf(m2).dims.get(.L));
-
-    const m_float = Scalar(f32, .{ .L = 1 }, .{});
-    const m3 = m_float{ .value = -42.5 };
-    try std.testing.expectEqual(42.5, m3.abs().value);
-}
-
-test "Pow" {
-    const Meter = Scalar(i128, .{ .L = 1 }, .{});
-    const d = Meter{ .value = 4 };
-
-    const area = d.pow(2);
-    try std.testing.expectEqual(16, area.value);
-    try std.testing.expectEqual(2, @TypeOf(area).dims.get(.L));
-
-    const volume = d.pow(3);
-    try std.testing.expectEqual(64, volume.value);
-    try std.testing.expectEqual(3, @TypeOf(volume).dims.get(.L));
-
-    // Float test
-    const MeterF = Scalar(f32, .{ .L = 1 }, .{});
-    const d_f = MeterF{ .value = 2.0 };
-    const area_f = d_f.pow(3);
-    try std.testing.expectEqual(8.0, area_f.value);
-    try std.testing.expectEqual(3, @TypeOf(area_f).dims.get(.L));
-}
-
-test "mul comptime_int" {
-    const Meter = Scalar(i128, .{ .L = 1 }, .{});
-    const d = Meter{ .value = 7 };
-
-    const scaled = d.mul(3); // comptime_int → dimensionless
-    try std.testing.expectEqual(21, scaled.value);
-    try std.testing.expectEqual(1, @TypeOf(scaled).dims.get(.L));
-    try std.testing.expectEqual(0, @TypeOf(scaled).dims.get(.T));
-}
-
-test "mul comptime_float" {
-    const MeterF = Scalar(f64, .{ .L = 1 }, .{});
-    const d = MeterF{ .value = 4.0 };
-
-    const scaled = d.mul(2.5); // comptime_float → dimensionless
-    try std.testing.expectApproxEqAbs(10.0, scaled.value, 1e-9);
-    try std.testing.expectEqual(1, @TypeOf(scaled).dims.get(.L));
-}
-
-test "mul T (value type)" {
-    const MeterF = Scalar(f32, .{ .L = 1 }, .{});
-    const d = MeterF{ .value = 6.0 };
-    const factor: f32 = 0.5;
-
-    const scaled = d.mul(factor); // bare f32 → dimensionless
-    try std.testing.expectApproxEqAbs(3.0, scaled.value, 1e-6);
-    try std.testing.expectEqual(1, @TypeOf(scaled).dims.get(.L));
-}
-
-test "div comptime_int" {
-    const Meter = Scalar(i128, .{ .L = 1 }, .{});
-    const d = Meter{ .value = 100 };
-
-    const half = d.div(4); // comptime_int → dimensionless divisor
-    try std.testing.expectEqual(25, half.value);
-    try std.testing.expectEqual(1, @TypeOf(half).dims.get(.L));
-}
-
-test "div comptime_float" {
-    const MeterF = Scalar(f64, .{ .L = 1 }, .{});
-    const d = MeterF{ .value = 9.0 };
-
-    const r = d.div(3.0);
-    try std.testing.expectApproxEqAbs(3.0, r.value, 1e-9);
-    try std.testing.expectEqual(1, @TypeOf(r).dims.get(.L));
-}
-
-test "add/sub bare number on dimensionless scalar" {
-    // Bare numbers are dimensionless, so add/sub only works when Self is also dimensionless.
-    const DimLess = Scalar(i128, .{}, .{});
-    const a = DimLess{ .value = 10 };
-
-    const b = a.add(5); // comptime_int, both dimensionless → ok
-    try std.testing.expectEqual(15, b.value);
-
-    const c = a.sub(3);
-    try std.testing.expectEqual(7, c.value);
-}
-
-test "Imperial length scales" {
-    const Foot = Scalar(f64, .{ .L = 1 }, .{ .L = .ft });
-    const Meter = Scalar(f64, .{ .L = 1 }, .{});
-    const Inch = Scalar(f64, .{ .L = 1 }, .{ .L = .inch });
-    const CentiMeter = Scalar(f64, .{ .L = 1 }, .{ .L = .c });
-    const Mile = Scalar(f64, .{ .L = 1 }, .{ .L = .mi });
-    const KiloMeter = Scalar(f64, .{ .L = 1 }, .{ .L = .k });
-    const Yard = Scalar(f64, .{ .L = 1 }, .{ .L = .yd });
-
-    // 1 ft → 0.3048 m
-    const one_ft = Foot{ .value = 1.0 };
-    try std.testing.expectApproxEqAbs(0.3048, one_ft.to(Meter).value, 1e-9);
-
-    // 12 in → 1 ft
-    const twelve_in = Inch{ .value = 12.0 };
-    try std.testing.expectApproxEqAbs(1.0, twelve_in.to(Foot).value, 1e-9);
-
-    // 1 in → 2.54 cm
-    const one_in = Inch{ .value = 1.0 };
-    try std.testing.expectApproxEqAbs(2.54, one_in.to(CentiMeter).value, 1e-9);
-
-    // 1 mi → 1.609344 km
-    const one_mi = Mile{ .value = 1.0 };
-    try std.testing.expectApproxEqAbs(1.609344, one_mi.to(KiloMeter).value, 1e-9);
-
-    // 3 ft → 1 yd
-    const three_ft = Foot{ .value = 3.0 };
-    try std.testing.expectApproxEqAbs(1.0, three_ft.to(Yard).value, 1e-9);
-}
-
-test "Imperial mass scales" {
-    const Pound = Scalar(f64, .{ .M = 1 }, .{ .M = .lb });
-    const KiloGram = Scalar(f64, .{ .M = 1 }, .{ .M = .k });
-    const Ounce = Scalar(f64, .{ .M = 1 }, .{ .M = .oz });
-    const Stone = Scalar(f64, .{ .M = 1 }, .{ .M = .st });
-
-    // 1 lb → ~0.453592 kg
-    const one_lb = Pound{ .value = 1.0 };
-    try std.testing.expectApproxEqAbs(0.45359237, one_lb.to(KiloGram).value, 1e-6);
-
-    // 16 oz → 1 lb
-    const sixteen_oz = Ounce{ .value = 16.0 };
-    try std.testing.expectApproxEqAbs(1.0, sixteen_oz.to(Pound).value, 1e-6);
-
-    // 1 stone → 14 lb
-    const one_st = Stone{ .value = 1.0 };
-    try std.testing.expectApproxEqAbs(14.0, one_st.to(Pound).value, 1e-4);
-
-    // 2 lb + 8 oz → 2.5 lb
-    const two_lb = Pound{ .value = 2.0 };
-    const eight_oz = Ounce{ .value = 8.0 };
-    const total = two_lb.add(eight_oz).to(Pound);
-    try std.testing.expectApproxEqAbs(2.5, total.value, 1e-6);
-}
-
-test "comparisons with comptime_int on dimensionless scalar" {
-    const DimLess = Scalar(i128, .{}, .{});
-    const x = DimLess{ .value = 42 };
-
-    try std.testing.expect(x.eq(42));
-    try std.testing.expect(x.ne(0));
-    try std.testing.expect(x.gt(10));
-    try std.testing.expect(x.gte(42));
-    try std.testing.expect(x.lt(100));
-    try std.testing.expect(x.lte(42));
-}

src/Scales.zig

@@ -1,5 +1,4 @@
 const std = @import("std");
-const hlp = @import("helper.zig");
 const Dimensions = @import("Dimensions.zig");
 const Dimension = @import("Dimensions.zig").Dimension;
 
@@ -56,35 +55,36 @@ pub const UnitScale = enum(isize) {
     // Undefined
     _,
 
-    pub inline fn str(self: @This()) []const u8 {
+    pub fn str(self: @This()) []const u8 {
         var buf: [16]u8 = undefined;
         return switch (self) {
-            inline .none => "",
-            inline .P, .T, .G, .M, .k, .h, .da, .d, .c, .m, .u, .n, .p, .f, .min, .hour, .year, .inch, .ft, .yd, .mi, .oz, .lb, .st => @tagName(self),
+            .none => "",
+            .P, .T, .G, .M, .k, .h, .da, .d, .c, .m, .u, .n, .p, .f, .min, .year, .inch, .ft, .yd, .mi, .oz, .lb, .st => @tagName(self),
+            .hour => "h",
             else => std.fmt.bufPrint(&buf, "[{d}]", .{@intFromEnum(self)}) catch "[]", // This cannot be inline because of non exhaustive enum, but that's ok, it is just str, not calculation
         };
     }
 
-    pub inline fn getFactor(self: @This()) comptime_float {
-        return comptime switch (self) {
+    pub fn getFactor(self: @This()) comptime_float {
+        return switch (self) {
             // Standard SI Exponents
-            inline .P, .T, .G, .M, .k, .h, .da, .none, .d, .c, .m, .u, .n, .p, .f => std.math.pow(f64, 10.0, @floatFromInt(@intFromEnum(self))),
+            .P, .T, .G, .M, .k, .h, .da, .none, .d, .c, .m, .u, .n, .p, .f => std.math.pow(f64, 10.0, @floatFromInt(@intFromEnum(self))),
 
             // Time Factors
-            inline .min, .hour, .year => @floatFromInt(@intFromEnum(self)),
+            .min, .hour, .year => @floatFromInt(@intFromEnum(self)),
 
             // Imperial Length (metres)
-            inline .inch => 0.0254,
-            inline .ft => 0.3048,
-            inline .yd => 0.9144,
-            inline .mi => 1609.344,
+            .inch => 0.0254,
+            .ft => 0.3048,
+            .yd => 0.9144,
+            .mi => 1609.344,
 
             // Imperial Mass (grams — base unit for M is gram, i.e. .none = 1 g)
-            inline .oz => 28.3495231,
-            inline .lb => 453.59237,
-            inline .st => 6350.29318,
+            .oz => 28.3495231,
+            .lb => 453.59237,
+            .st => 6350.29318,
 
-            inline else => @floatFromInt(@intFromEnum(self)),
+            else => @floatFromInt(@intFromEnum(self)),
         };
     }
 };
@@ -98,40 +98,46 @@ data: std.EnumArray(Dimension, UnitScale),
 /// Unspecified dimensions default to `.none` (factor 1).
 pub fn init(comptime init_val: ArgOpts) Self {
     comptime var s = Self{ .data = std.EnumArray(Dimension, UnitScale).initFill(.none) };
-    inline for (std.meta.fields(@TypeOf(init_val))) |f| {
-        if (comptime hlp.isInt(@TypeOf(@field(init_val, f.name))))
+    for (std.meta.fields(@TypeOf(init_val))) |f| {
+        if (comptime @typeInfo(@TypeOf(@field(init_val, f.name))) == .comptime_int)
             s.data.set(@field(Dimension, f.name), @enumFromInt(@field(init_val, f.name)))
         else
             s.data.set(@field(Dimension, f.name), @field(init_val, f.name));
     }
-    return s;
+    return comptime s;
 }
 
-pub fn initFill(comptime val: UnitScale) Self {
-    return comptime .{ .data = std.EnumArray(Dimension, UnitScale).initFill(val) };
+pub fn initFill(val: UnitScale) Self {
+    return .{ .data = std.EnumArray(Dimension, UnitScale).initFill(val) };
 }
 
-pub fn get(comptime self: Self, comptime key: Dimension) UnitScale {
-    return comptime self.data.get(key);
+pub fn get(self: Self, key: Dimension) UnitScale {
+    return self.data.get(key);
 }
 
-pub fn set(comptime self: *Self, comptime key: Dimension, comptime val: UnitScale) void {
-    comptime self.data.set(key, val);
+pub fn set(self: *Self, key: Dimension, val: UnitScale) void {
+    self.data.set(key, val);
+}
+
+pub fn eql(self: Self, other: Self) bool {
+    for (self.data.values, other.data.values) |l, r|
+        if (l != r) return false;
+    return true;
 }
 
 pub fn argsOpt(self: Self) ArgOpts {
     var args: ArgOpts = undefined;
-    inline for (std.enums.values(Dimension)) |d|
+    for (std.enums.values(Dimension)) |d|
         @field(args, @tagName(d)) = self.get(d);
     return args;
 }
 
 /// Compute the combined scale factor for a given dimension signature.
 /// Each dimension's prefix is raised to its exponent and multiplied together.
-pub inline fn getFactor(comptime s: Self, comptime d: Dimensions) comptime_float {
+pub fn getFactor(s: Self, d: Dimensions) comptime_float {
     var factor: f64 = 1.0;
     for (std.enums.values(Dimension)) |dim| {
-        const power = comptime d.get(dim);
+        const power = d.get(dim);
         if (power == 0) continue;
 
         const base = s.get(dim).getFactor();
@@ -145,5 +151,5 @@ pub inline fn getFactor(comptime s: Self, comptime d: Dimensions) comptime_float
                 factor /= base;
         }
     }
-    return comptime factor;
+    return factor;
 }

src/UnitParser.zig

@@ -0,0 +1,145 @@
+const std = @import("std");
+const Dimensions = @import("Dimensions.zig");
+const Scales = @import("Scales.zig");
+
+/// A container returning the separated arguments needed to construct a Tensor.
+pub const ParsedUnit = struct {
+    dims: Dimensions.ArgOpts = .{},
+    scales: Scales.ArgOpts = .{},
+};
+
+pub const UnitParseError = error{
+    UnknownBaseUnit,
+    UnknownPrefix,
+    InvalidExponent,
+    EmptyStr,
+};
+
+/// Parses strings like "km/s^2", "m", "kg*m/s^2", "1/min".
+/// Evaluates entirely at comptime.
+pub fn parseUnit(str: []const u8) !ParsedUnit {
+    if (str.len == 0) return UnitParseError.EmptyStr;
+
+    var parsed: ParsedUnit = .{ .dims = .{}, .scales = .{} };
+
+    // We need to track if we are after a '/' to flip exponents to negative
+    var is_denominator = false;
+
+    // Manual iteration to handle '/' properly
+    var cursor: usize = 0;
+    while (cursor < str.len) {
+        // Find the next segment
+        const segment_start = cursor;
+        while (cursor < str.len and str[cursor] != '/' and str[cursor] != '.' and str[cursor] != '*') : (cursor += 1) {}
+        const segment = str[segment_start..cursor];
+
+        if (segment.len > 0) {
+            try parseSegment(segment, &parsed, is_denominator);
+        }
+
+        if (cursor < str.len) {
+            if (str[cursor] == '/') {
+                is_denominator = true;
+            }
+            cursor += 1; // skip the separator
+        }
+    }
+
+    return parsed;
+}
+
+fn parseSegment(segment: []const u8, parsed: *ParsedUnit, is_denominator: bool) !void {
+    var scale: Scales.UnitScale = .none;
+    var found_scale = false;
+    var active_dim: ?Dimensions.Dimension = null;
+
+    // 1. Try to find a Scale + Dimension pair (e.g., "mm", "km")
+    inline for (std.enums.values(Scales.UnitScale)) |sca| {
+        const s_str = sca.str();
+        if (s_str.len > 0 and std.mem.startsWith(u8, segment, s_str)) {
+            // Check if it's a "Unit-as-Scale" (hour, min) or a prefix (k, m, c)
+            switch (sca) {
+                .hour, .min, .year => {
+                    // These are dimensions themselves (Time)
+                    if (segment.len == s_str.len or (segment.len > s_str.len and (segment[s_str.len] == '^' or (segment[s_str.len] >= '0' and segment[s_str.len] <= '9')))) {
+                        scale = sca;
+                        active_dim = .T;
+                        found_scale = true;
+                    }
+                },
+                else => {
+                    // Standard prefixes: Must be followed by a valid dimension unit
+                    inline for (std.enums.values(Dimensions.Dimension)) |dim| {
+                        if (std.mem.startsWith(u8, segment[s_str.len..], dim.unit())) {
+                            scale = sca;
+                            active_dim = dim;
+                            found_scale = true;
+                            break;
+                        }
+                    }
+                },
+            }
+        }
+        if (found_scale) break;
+    }
+
+    // 2. If no scale prefix was found, try identifying as a pure Dimension (e.g., "m", "s")
+    if (!found_scale) {
+        inline for (std.enums.values(Dimensions.Dimension)) |dim| {
+            if (std.mem.startsWith(u8, segment, dim.unit())) {
+                active_dim = dim;
+                break;
+            }
+        }
+    }
+
+    const dimen = active_dim orelse return UnitParseError.UnknownBaseUnit;
+
+    // 3. Determine where the exponent starts
+    // If it was a Time Scale (like 'h'), the exponent starts after 'h'
+    // If it was a Prefix + Dim (like 'km'), it starts after 'km'
+    const unit_part_len = if (found_scale)
+        (if (scale == .hour or scale == .min or scale == .year) scale.str().len else scale.str().len + dimen.unit().len)
+    else
+        dimen.unit().len;
+
+    const expo_str = segment[unit_part_len..];
+
+    // 4. Parse Exponent
+    var expo: i32 = 1;
+    if (expo_str.len > 0) {
+        const cleaned_expo = if (expo_str[0] == '^') expo_str[1..] else expo_str;
+        expo = std.fmt.parseInt(i32, cleaned_expo, 10) catch return UnitParseError.InvalidExponent;
+    }
+
+    if (is_denominator) expo *= -1;
+
+    // 5. Assign to struct
+    inline for (std.meta.fields(Dimensions.ArgOpts)) |f| {
+        if (std.mem.eql(u8, f.name, @tagName(dimen))) {
+            @field(parsed.dims, f.name) += expo;
+            @field(parsed.scales, f.name) = scale;
+        }
+    }
+}
+
+inline fn testParser(
+    comptime str: []const u8,
+    comptime expected_dims: Dimensions.ArgOpts,
+    comptime expected_scales: Scales.ArgOpts,
+) !void {
+    const unit = comptime try parseUnit(str);
+    if (comptime !Dimensions.init(expected_dims).eql(Dimensions.init(unit.dims))) return error.WrongDims;
+    if (comptime !Scales.init(expected_scales).eql(Scales.init(unit.scales))) return error.WrongScales;
+}
+
+test "parseUnit" {
+    @setEvalBranchQuota(10000);
+    try testParser("m", .{ .L = 1 }, .{});
+    try testParser("s", .{ .T = 1 }, .{});
+    try testParser("mm", .{ .L = 1 }, .{ .L = .m });
+    try testParser("m/s", .{ .L = 1, .T = -1 }, .{});
+    try testParser("m1/s2/kg", .{ .L = 1, .T = -2, .M = -1 }, .{ .M = .k });
+    try testParser("km/h", .{ .L = 1, .T = -1 }, .{ .L = .k, .T = .hour });
+    try testParser("m.s^-1", .{ .L = 1, .T = -1 }, .{});
+}

src/Vector.zig

@@ -1,831 +0,0 @@
-const std = @import("std");
-const hlp = @import("helper.zig");
-
-const Scalar = @import("Scalar.zig").Scalar;
-const Scales = @import("Scales.zig");
-const UnitScale = Scales.UnitScale;
-const Dimensions = @import("Dimensions.zig");
-const Dimension = Dimensions.Dimension;
-
-/// A fixed-size array of `len` elements sharing the same dimension and scale as scalar type `Q`.
-pub fn Vector(comptime len: usize, comptime Q: type) type {
-    const T = Q.ValueType;
-
-    return struct {
-        data: [len]T,
-
-        const Self = @This();
-        pub const ScalarType = Q;
-        pub const ValueType = T;
-        pub const dims: Dimensions = Q.dims;
-        pub const scales = Q.scales;
-
-        pub const zero = initDefault(0);
-        pub const one = initDefault(1);
-
-        pub fn initDefault(v: T) Self {
-            var data: [len]T = undefined;
-            inline for (&data) |*item| item.* = v;
-            return .{ .data = data };
-        }
-
-        // -------------------------------------------------------------------
-        // Internal: scalar-rhs normalisation (mirrors Scalar.zig)
-        // -------------------------------------------------------------------
-
-        /// Resolved Scalar type for a scalar operand (bare number or Scalar).
-        /// Passing another Vector here is a compile error.
-        inline fn ScalarRhsT(comptime Rhs: type) type {
-            if (comptime switch (@typeInfo(Rhs)) {
-                .@"struct", .@"enum", .@"union", .@"opaque" => @hasDecl(Rhs, "ScalarType"),
-                else => false,
-            })
-                @compileError(
-                    "Expected a Scalar or bare number; got a Vector. " ++
-                        "Use mul / div for element-wise vector operations.",
-                );
-            return hlp.rhsScalarType(T, Rhs);
-        }
-
-        /// Normalise a scalar rhs (bare number → dimensionless Scalar).
-        inline fn scalarRhs(r: anytype) ScalarRhsT(@TypeOf(r)) {
-            return hlp.toRhsScalar(T, r);
-        }
-
-        // -------------------------------------------------------------------
-        // Vector–Vector operations  (rhs must be a Vector of the same length)
-        // -------------------------------------------------------------------
-
-        /// Element-wise addition. Dimensions must match; scales resolve to the finer of the two.
-        pub inline fn add(self: Self, rhs: anytype) Vector(len, Scalar(
-            T,
-            dims.argsOpt(),
-            hlp.finerScales(Self, @TypeOf(rhs)).argsOpt(),
-        )) {
-            const Tr = @TypeOf(rhs);
-            var res: Vector(len, Scalar(
-                T,
-                dims.argsOpt(),
-                hlp.finerScales(Self, @TypeOf(rhs)).argsOpt(),
-            )) = undefined;
-            inline for (self.data, 0..) |v, i| {
-                const q = (Q{ .value = v }).add(Tr.ScalarType{ .value = rhs.data[i] });
-                res.data[i] = q.value;
-            }
-            return res;
-        }
-
-        /// Element-wise subtraction. Dimensions must match; scales resolve to the finer of the two.
-        pub inline fn sub(self: Self, rhs: anytype) Vector(len, Scalar(
-            T,
-            dims.argsOpt(),
-            hlp.finerScales(Self, @TypeOf(rhs)).argsOpt(),
-        )) {
-            const Tr = @TypeOf(rhs);
-            var res: Vector(len, Scalar(
-                T,
-                dims.argsOpt(),
-                hlp.finerScales(Self, @TypeOf(rhs)).argsOpt(),
-            )) = undefined;
-            inline for (self.data, 0..) |v, i| {
-                const q = (Q{ .value = v }).sub(Tr.ScalarType{ .value = rhs.data[i] });
-                res.data[i] = q.value;
-            }
-            return res;
-        }
-
-        /// Element-wise division. Dimension exponents are subtracted per component.
-        pub inline fn div(
-            self: Self,
-            rhs: anytype,
-        ) Vector(len, Scalar(
-            T,
-            dims.sub(@TypeOf(rhs).dims).argsOpt(),
-            hlp.finerScales(Self, @TypeOf(rhs)).argsOpt(),
-        )) {
-            const Tr = @TypeOf(rhs);
-            var res: Vector(len, Scalar(
-                T,
-                dims.sub(Tr.dims).argsOpt(),
-                hlp.finerScales(Self, @TypeOf(rhs)).argsOpt(),
-            )) = undefined;
-            inline for (self.data, 0..) |v, i| {
-                const q = (Q{ .value = v }).div(Tr.ScalarType{ .value = rhs.data[i] });
-                res.data[i] = q.value;
-            }
-            return res;
-        }
-
-        /// Element-wise multiplication. Dimension exponents are summed per component.
-        pub inline fn mul(
-            self: Self,
-            rhs: anytype,
-        ) Vector(len, Scalar(
-            T,
-            dims.add(@TypeOf(rhs).dims).argsOpt(),
-            hlp.finerScales(Self, @TypeOf(rhs)).argsOpt(),
-        )) {
-            const Tr = @TypeOf(rhs);
-            var res: Vector(len, Scalar(
-                T,
-                dims.add(Tr.dims).argsOpt(),
-                hlp.finerScales(Self, @TypeOf(rhs)).argsOpt(),
-            )) = undefined;
-            inline for (self.data, 0..) |v, i| {
-                const q = (Q{ .value = v }).mul(Tr.ScalarType{ .value = rhs.data[i] });
-                res.data[i] = q.value;
-            }
-            return res;
-        }
-
-        // -------------------------------------------------------------------
-        // Vector–Scalar operations
-        // scalar may be: Scalar, T, comptime_int, comptime_float
-        // -------------------------------------------------------------------
-
-        /// Divide every component by a single scalar. Dimensions are subtracted.
-        /// `scalar` may be a Scalar, `T`, `comptime_int`, or `comptime_float`.
-        pub inline fn divScalar(
-            self: Self,
-            scalar: anytype,
-        ) Vector(len, Scalar(
-            T,
-            dims.sub(ScalarRhsT(@TypeOf(scalar)).dims).argsOpt(),
-            hlp.finerScales(Self, ScalarRhsT(@TypeOf(scalar))).argsOpt(),
-        )) {
-            const s_norm = scalarRhs(scalar);
-            const SN = @TypeOf(s_norm);
-            var res: Vector(len, Scalar(
-                T,
-                dims.sub(SN.dims).argsOpt(),
-                hlp.finerScales(Self, SN).argsOpt(),
-            )) = undefined;
-            inline for (self.data, 0..) |v, i|
-                res.data[i] = (Q{ .value = v }).div(s_norm).value;
-            return res;
-        }
-
-        /// Multiply every component by a single scalar. Dimensions are summed.
-        /// `scalar` may be a Scalar, `T`, `comptime_int`, or `comptime_float`.
-        pub inline fn mulScalar(
-            self: Self,
-            scalar: anytype,
-        ) Vector(len, Scalar(
-            T,
-            dims.add(ScalarRhsT(@TypeOf(scalar)).dims).argsOpt(),
-            hlp.finerScales(Self, ScalarRhsT(@TypeOf(scalar))).argsOpt(),
-        )) {
-            const s_norm = scalarRhs(scalar);
-            const SN = @TypeOf(s_norm);
-            var res: Vector(len, Scalar(
-                T,
-                dims.add(SN.dims).argsOpt(),
-                hlp.finerScales(Self, SN).argsOpt(),
-            )) = undefined;
-            inline for (self.data, 0..) |v, i|
-                res.data[i] = (Q{ .value = v }).mul(s_norm).value;
-            return res;
-        }
-
-        // -------------------------------------------------------------------
-        // Dot / Cross
-        // -------------------------------------------------------------------
-
-        /// Standard dot product. Dimensions are summed (e.g., Force * Distance = Energy).
-        /// Returns a Scalar type with the combined dimensions and finest scale.
-        pub inline fn dot(self: Self, rhs: anytype) Scalar(
-            T,
-            dims.add(@TypeOf(rhs).dims).argsOpt(),
-            hlp.finerScales(Self, @TypeOf(rhs)).argsOpt(),
-        ) {
-            const Tr = @TypeOf(rhs);
-
-            var sum: T = 0;
-            inline for (self.data, 0..) |v, i| {
-                const q_lhs = Q{ .value = v };
-                const q_rhs = Tr.ScalarType{ .value = rhs.data[i] };
-                sum += q_lhs.mul(q_rhs).value;
-            }
-            return .{ .value = sum };
-        }
-
-        /// 3D Cross product. Dimensions are summed.
-        /// Only valid for vectors of length 3.
-        pub inline fn cross(self: Self, rhs: anytype) Vector(3, Scalar(
-            T,
-            dims.add(@TypeOf(rhs).dims).argsOpt(),
-            hlp.finerScales(Self, @TypeOf(rhs)).argsOpt(),
-        )) {
-            if (comptime len != 3)
-                @compileError("Cross product is only defined for Vector(3, ...)");
-
-            const Tr = @TypeOf(rhs);
-            const ResScalar = Scalar(T, dims.add(Tr.dims).argsOpt(), hlp.finerScales(Self, Tr).argsOpt());
-            const ResVec = Vector(3, ResScalar);
-
-            // Calculation: [y1*z2 - z1*y2, z1*x2 - x1*z2, x1*y2 - y1*x2]
-            const s1 = Q{ .value = self.data[0] };
-            const s2 = Q{ .value = self.data[1] };
-            const s3 = Q{ .value = self.data[2] };
-
-            const o1 = Tr.ScalarType{ .value = rhs.data[0] };
-            const o2 = Tr.ScalarType{ .value = rhs.data[1] };
-            const o3 = Tr.ScalarType{ .value = rhs.data[2] };
-
-            return ResVec{
-                .data = .{
-                    s2.mul(o3).sub(s3.mul(o2)).value,
-                    s3.mul(o1).sub(s1.mul(o3)).value,
-                    s1.mul(o2).sub(s2.mul(o1)).value,
-                },
-            };
-        }
-
-        // -------------------------------------------------------------------
-        // Unary
-        // -------------------------------------------------------------------
-
-        /// Returns a vector where each component is the absolute value of the original.
-        pub inline fn abs(self: Self) Self {
-            var res: Self = undefined;
-            inline for (self.data, 0..) |v, i| {
-                const q = Q{ .value = v };
-                res.data[i] = q.abs().value;
-            }
-            return res;
-        }
-
-        /// Returns a vector where each component is the absolute value of the original.
-        pub inline fn sqrt(self: Self) Self {
-            var res: Self = undefined;
-            inline for (self.data, 0..) |v, i| {
-                const q = Q{ .value = v };
-                res.data[i] = q.sqrt().value;
-            }
-            return res;
-        }
-
-        /// Multiplies all components of the vector together.
-        /// Resulting dimensions are (Original Dims * len).
-        pub inline fn product(self: Self) Scalar(
-            T,
-            dims.scale(len).argsOpt(),
-            scales.argsOpt(),
-        ) {
-            var res_val: T = 1;
-            if (comptime hlp.isInt(T)) {
-                inline for (self.data) |v|
-                    res_val = res_val *| v;
-            } else inline for (self.data) |v|
-                res_val *= v;
-            return .{ .value = res_val };
-        }
-
-        /// Raises every component to a compile-time integer power.
-        /// Dimensions are scaled by the exponent.
-        pub inline fn pow(self: Self, comptime exp: comptime_int) Vector(
-            len,
-            Scalar(
-                T,
-                dims.scale(exp).argsOpt(),
-                scales.argsOpt(),
-            ),
-        ) {
-            const ResScalar = Scalar(T, dims.scale(exp).argsOpt(), scales.argsOpt());
-            var res: Vector(len, ResScalar) = undefined;
-            inline for (self.data, 0..) |v, i| {
-                const q = Q{ .value = v };
-                res.data[i] = q.pow(exp).value;
-            }
-            return res;
-        }
-
-        /// Negate all components. Dimensions are preserved.
-        pub fn negate(self: Self) Self {
-            var res: Self = undefined;
-            inline for (self.data, 0..) |v, i|
-                res.data[i] = -v;
-            return res;
-        }
-
-        // -------------------------------------------------------------------
-        // Conversion
-        // -------------------------------------------------------------------
-
-        /// Convert all components to a compatible scalar type. Compile error on dimension mismatch.
-        pub inline fn to(self: Self, comptime DestQ: type) Vector(len, DestQ) {
-            var res: Vector(len, DestQ) = undefined;
-            inline for (self.data, 0..) |v, i|
-                res.data[i] = (Q{ .value = v }).to(DestQ).value;
-            return res;
-        }
-
-        // -------------------------------------------------------------------
-        // Length
-        // -------------------------------------------------------------------
-
-        /// Sum of squared components. Cheaper than `length` — use for comparisons.
-        pub inline fn lengthSqr(self: Self) T {
-            var sum: T = 0;
-            inline for (self.data) |v|
-                sum += v * v;
-            return sum;
-        }
-
-        /// Euclidean length. Integer types use integer sqrt (truncated).
-        pub inline fn length(self: Self) T {
-            const len_sq = self.lengthSqr();
-
-            if (comptime @typeInfo(T) == .int) {
-                const UnsignedT = @Int(.unsigned, @typeInfo(T).int.bits);
-                const u_len_sq = @as(UnsignedT, @intCast(len_sq));
-                return @as(T, @intCast(std.math.sqrt(u_len_sq)));
-            } else {
-                return @sqrt(len_sq);
-            }
-        }
-
-        // -------------------------------------------------------------------
-        // Vector–Vector comparisons
-        // -------------------------------------------------------------------
-
-        /// Returns true only if all components are equal after scale resolution.
-        pub inline fn eqAll(self: Self, rhs: anytype) bool {
-            const Tr = @TypeOf(rhs);
-            if (comptime !dims.eql(Tr.dims))
-                @compileError("Dimension mismatch in eq: " ++ dims.str() ++ " vs " ++ Tr.dims.str());
-
-            inline for (self.data, 0..) |v, i| {
-                const lhs_q = Q{ .value = v };
-                const rhs_q = Tr.ScalarType{ .value = rhs.data[i] };
-                if (!lhs_q.eq(rhs_q)) return false;
-            }
-            return true;
-        }
-
-        /// Returns true if any component differs after scale resolution.
-        pub inline fn neAll(self: Self, rhs: anytype) bool {
-            return !self.eqAll(rhs);
-        }
-
-        /// Element-wise "Equal". Returns an array of booleans.
-        pub inline fn eq(self: Self, rhs: anytype) [len]bool {
-            const Tr = @TypeOf(rhs);
-            var res: [len]bool = undefined;
-            inline for (self.data, 0..) |v, i|
-                res[i] = (Q{ .value = v }).eq(Tr.ScalarType{ .value = rhs.data[i] });
-            return res;
-        }
-
-        /// Element-wise "Not Equal". Returns an array of booleans.
-        pub inline fn ne(self: Self, rhs: anytype) [len]bool {
-            const Tr = @TypeOf(rhs);
-            var res: [len]bool = undefined;
-            inline for (self.data, 0..) |v, i|
-                res[i] = (Q{ .value = v }).ne(Tr.ScalarType{ .value = rhs.data[i] });
-            return res;
-        }
-
-        /// Element-wise "Greater Than". Returns an array of booleans.
-        pub inline fn gt(self: Self, rhs: anytype) [len]bool {
-            const Tr = @TypeOf(rhs);
-            var res: [len]bool = undefined;
-            inline for (self.data, 0..) |v, i|
-                res[i] = (Q{ .value = v }).gt(Tr.ScalarType{ .value = rhs.data[i] });
-            return res;
-        }
-
-        /// Element-wise "Greater Than or Equal". Returns an array of booleans.
-        pub inline fn gte(self: Self, rhs: anytype) [len]bool {
-            const Tr = @TypeOf(rhs);
-            var res: [len]bool = undefined;
-            inline for (self.data, 0..) |v, i|
-                res[i] = (Q{ .value = v }).gte(Tr.ScalarType{ .value = rhs.data[i] });
-            return res;
-        }
-
-        /// Element-wise "Less Than". Returns an array of booleans.
-        pub inline fn lt(self: Self, rhs: anytype) [len]bool {
-            const Tr = @TypeOf(rhs);
-            var res: [len]bool = undefined;
-            inline for (self.data, 0..) |v, i|
-                res[i] = (Q{ .value = v }).lt(Tr.ScalarType{ .value = rhs.data[i] });
-            return res;
-        }
-
-        /// Element-wise "Less Than or Equal". Returns an array of booleans.
-        pub inline fn lte(self: Self, rhs: anytype) [len]bool {
-            const Tr = @TypeOf(rhs);
-            var res: [len]bool = undefined;
-            inline for (self.data, 0..) |v, i|
-                res[i] = (Q{ .value = v }).lte(Tr.ScalarType{ .value = rhs.data[i] });
-            return res;
-        }
-
-        // -------------------------------------------------------------------
-        // Vector–Scalar comparisons
-        // scalar may be: Scalar, T, comptime_int, comptime_float
-        // -------------------------------------------------------------------
-
-        /// Compares every element in the vector to a single scalar for equality.
-        /// Returns an array of booleans [len]bool. Dimensions must match; scales are auto-resolved.
-        pub inline fn eqScalar(self: Self, scalar: anytype) [len]bool {
-            var res: [len]bool = undefined;
-            inline for (self.data, 0..) |v, i|
-                res[i] = (Q{ .value = v }).eq(scalar);
-            return res;
-        }
-
-        /// Compares every element in the vector to a single scalar for inequality.
-        /// Returns an array of booleans [len]bool. Dimensions must match; scales are auto-resolved.
-        pub inline fn neScalar(self: Self, scalar: anytype) [len]bool {
-            var res: [len]bool = undefined;
-            inline for (self.data, 0..) |v, i|
-                res[i] = (Q{ .value = v }).ne(scalar);
-            return res;
-        }
-
-        /// Checks if each element in the vector is strictly greater than the given scalar.
-        /// Returns an array of booleans [len]bool.
-        pub inline fn gtScalar(self: Self, scalar: anytype) [len]bool {
-            var res: [len]bool = undefined;
-            inline for (self.data, 0..) |v, i|
-                res[i] = (Q{ .value = v }).gt(scalar);
-            return res;
-        }
-
-        /// Checks if each element in the vector is greater than or equal to the given scalar.
-        /// Returns an array of booleans [len]bool.
-        pub inline fn gteScalar(self: Self, scalar: anytype) [len]bool {
-            var res: [len]bool = undefined;
-            inline for (self.data, 0..) |v, i|
-                res[i] = (Q{ .value = v }).gte(scalar);
-            return res;
-        }
-
-        /// Checks if each element in the vector is strictly less than the given scalar.
-        /// Returns an array of booleans [len]bool.
-        pub inline fn ltScalar(self: Self, scalar: anytype) [len]bool {
-            var res: [len]bool = undefined;
-            inline for (self.data, 0..) |v, i|
-                res[i] = (Q{ .value = v }).lt(scalar);
-            return res;
-        }
-
-        /// Checks if each element in the vector is less than or equal to the given scalar.
-        /// Returns an array of booleans [len]bool.
-        pub inline fn lteScalar(self: Self, scalar: anytype) [len]bool {
-            var res: [len]bool = undefined;
-            inline for (self.data, 0..) |v, i|
-                res[i] = (Q{ .value = v }).lte(scalar);
-            return res;
-        }
-
-        // -------------------------------------------------------------------
-        // Formatting
-        // -------------------------------------------------------------------
-
-        pub fn formatNumber(
-            self: Self,
-            writer: *std.Io.Writer,
-            options: std.fmt.Number,
-        ) !void {
-            try writer.writeAll("(");
-            for (self.data, 0..) |v, i| {
-                if (i > 0) try writer.writeAll(", ");
-                switch (@typeInfo(T)) {
-                    .float, .comptime_float => try writer.printFloat(v, options),
-                    .int, .comptime_int => try writer.printInt(v, 10, .lower, .{
-                        .width = options.width,
-                        .alignment = options.alignment,
-                        .fill = options.fill,
-                        .precision = options.precision,
-                    }),
-                    else => unreachable,
-                }
-            }
-            try writer.writeAll(")");
-            var first = true;
-            inline for (std.enums.values(Dimension)) |bu| {
-                const v = dims.get(bu);
-                if (comptime v == 0) continue;
-                if (!first)
-                    try writer.writeAll(".");
-
-                first = false;
-
-                const uscale = scales.get(bu);
-                if (bu == .T and (uscale == .min or uscale == .hour or uscale == .year))
-                    try writer.print("{s}", .{uscale.str()})
-                else
-                    try writer.print("{s}{s}", .{ uscale.str(), bu.unit() });
-
-                if (v != 1)
-                    try hlp.printSuperscript(writer, v);
-            }
-        }
-    };
-}
-
-test "Format VectorX" {
-    const MeterPerSecondSq = Scalar(f32, .{ .L = 1, .T = -2 }, .{ .T = .n });
-    const KgMeterPerSecond = Scalar(f32, .{ .M = 1, .L = 1, .T = -1 }, .{ .M = .k });
-
-    const accel = MeterPerSecondSq.Vec3.initDefault(9.81);
-    const momentum = KgMeterPerSecond.Vec3{ .data = .{ 43, 0, 11 } };
-
-    var buf: [64]u8 = undefined;
-    var res = try std.fmt.bufPrint(&buf, "{d}", .{accel});
-    try std.testing.expectEqualStrings("(9.81, 9.81, 9.81)m.ns⁻²", res);
-
-    res = try std.fmt.bufPrint(&buf, "{d:.2}", .{momentum});
-    try std.testing.expectEqualStrings("(43.00, 0.00, 11.00)m.kg.s⁻¹", res);
-}
-
-test "VecX Init and Basic Arithmetic" {
-    const Meter = Scalar(i32, .{ .L = 1 }, .{});
-    const Vec3M = Meter.Vec3;
-
-    // Test zero, one, initDefault
-    const v_zero = Vec3M.zero;
-    try std.testing.expectEqual(0, v_zero.data[0]);
-    try std.testing.expectEqual(0, v_zero.data[1]);
-    try std.testing.expectEqual(0, v_zero.data[2]);
-
-    const v_one = Vec3M.one;
-    try std.testing.expectEqual(1, v_one.data[0]);
-    try std.testing.expectEqual(1, v_one.data[1]);
-    try std.testing.expectEqual(1, v_one.data[2]);
-
-    const v_def = Vec3M.initDefault(5);
-    try std.testing.expectEqual(5, v_def.data[0]);
-    try std.testing.expectEqual(5, v_def.data[1]);
-    try std.testing.expectEqual(5, v_def.data[2]);
-
-    // Test add and sub
-    const v1 = Vec3M{ .data = .{ 10, 20, 30 } };
-    const v2 = Vec3M{ .data = .{ 2, 4, 6 } };
-
-    const added = v1.add(v2);
-    try std.testing.expectEqual(12, added.data[0]);
-    try std.testing.expectEqual(24, added.data[1]);
-    try std.testing.expectEqual(36, added.data[2]);
-
-    const subbed = v1.sub(v2);
-    try std.testing.expectEqual(8, subbed.data[0]);
-    try std.testing.expectEqual(16, subbed.data[1]);
-    try std.testing.expectEqual(24, subbed.data[2]);
-
-    // Test negate
-    const neg = v1.negate();
-    try std.testing.expectEqual(-10, neg.data[0]);
-    try std.testing.expectEqual(-20, neg.data[1]);
-    try std.testing.expectEqual(-30, neg.data[2]);
-}
-
-test "VecX Kinematics (Scalar Mul/Div)" {
-    const Meter = Scalar(i32, .{ .L = 1 }, .{});
-    const Second = Scalar(i32, .{ .T = 1 }, .{});
-    const Vec3M = Meter.Vec3;
-
-    const pos = Vec3M{ .data = .{ 100, 200, 300 } };
-    const time = Second{ .value = 10 };
-
-    // Vector divided by scalar (Velocity = Position / Time)
-    const vel = pos.divScalar(time);
-    try std.testing.expectEqual(10, vel.data[0]);
-    try std.testing.expectEqual(20, vel.data[1]);
-    try std.testing.expectEqual(30, vel.data[2]);
-    try std.testing.expectEqual(1, @TypeOf(vel).dims.get(.L));
-    try std.testing.expectEqual(-1, @TypeOf(vel).dims.get(.T));
-
-    // Vector multiplied by scalar (Position = Velocity * Time)
-    const new_pos = vel.mulScalar(time);
-    try std.testing.expectEqual(100, new_pos.data[0]);
-    try std.testing.expectEqual(200, new_pos.data[1]);
-    try std.testing.expectEqual(300, new_pos.data[2]);
-    try std.testing.expectEqual(1, @TypeOf(new_pos).dims.get(.L));
-    try std.testing.expectEqual(0, @TypeOf(new_pos).dims.get(.T));
-}
-
-test "VecX Element-wise Math and Scaling" {
-    const Meter = Scalar(i32, .{ .L = 1 }, .{});
-    const Vec3M = Meter.Vec3;
-
-    const v1 = Vec3M{ .data = .{ 10, 20, 30 } };
-    const v2 = Vec3M{ .data = .{ 2, 5, 10 } };
-
-    // Element-wise division
-    const div = v1.div(v2);
-    try std.testing.expectEqual(5, div.data[0]);
-    try std.testing.expectEqual(4, div.data[1]);
-    try std.testing.expectEqual(3, div.data[2]);
-    try std.testing.expectEqual(0, @TypeOf(div).dims.get(.L)); // M / M = Dimensionless
-}
-
-test "VecX Conversions" {
-    const KiloMeter = Scalar(i32, .{ .L = 1 }, .{ .L = .k });
-    const Meter = Scalar(i32, .{ .L = 1 }, .{});
-
-    const v_km = KiloMeter.Vec3{ .data = .{ 1, 2, 3 } };
-    const v_m = v_km.to(Meter);
-
-    try std.testing.expectEqual(1000, v_m.data[0]);
-    try std.testing.expectEqual(2000, v_m.data[1]);
-    try std.testing.expectEqual(3000, v_m.data[2]);
-
-    // Type checking the result
-    try std.testing.expectEqual(1, @TypeOf(v_m).dims.get(.L));
-    try std.testing.expectEqual(UnitScale.none, @TypeOf(v_m).scales.get(.L));
-}
-
-test "VecX Length" {
-    const MeterInt = Scalar(i32, .{ .L = 1 }, .{});
-    const MeterFloat = Scalar(f32, .{ .L = 1 }, .{});
-
-    // Integer length
-    // 3-4-5 triangle on XY plane
-    const v_int = MeterInt.Vec3{ .data = .{ 3, 4, 0 } };
-    try std.testing.expectEqual(25, v_int.lengthSqr());
-    try std.testing.expectEqual(5, v_int.length());
-
-    // Float length
-    const v_float = MeterFloat.Vec3{ .data = .{ 3.0, 4.0, 0.0 } };
-    try std.testing.expectApproxEqAbs(@as(f32, 25.0), v_float.lengthSqr(), 1e-4);
-    try std.testing.expectApproxEqAbs(@as(f32, 5.0), v_float.length(), 1e-4);
-}
-
-test "Vector Comparisons" {
-    const Meter = Scalar(f32, .{ .L = 1 }, .{});
-    const KiloMeter = Scalar(f32, .{ .L = 1 }, .{ .L = .k });
-
-    const v1 = Meter.Vec3{ .data = .{ 1000.0, 500.0, 0.0 } };
-    const v2 = KiloMeter.Vec3{ .data = .{ 1.0, 0.5, 0.0 } };
-    const v3 = KiloMeter.Vec3{ .data = .{ 1.0, 0.6, 0.0 } };
-
-    // 1. Equality (Whole vector)
-    try std.testing.expect(v1.eqAll(v2));
-    try std.testing.expect(v1.neAll(v3));
-
-    // 2. Element-wise Ordered Comparison
-    const higher = v3.gt(v1); // compares 1km, 0.6km, 0km vs 1000m, 500m, 0m
-    try std.testing.expectEqual(false, higher[0]); // 1km == 1000m
-    try std.testing.expectEqual(true, higher[1]); // 0.6km > 500m
-    try std.testing.expectEqual(false, higher[2]); // 0 == 0
-
-    // 3. Element-wise Equal Comparison
-    const equal = v3.eq(v1); // compares 1km, 0.6km, 0km vs 1000m, 500m, 0m
-    try std.testing.expectEqual(true, equal[0]); // 1km == 1000m
-    try std.testing.expectEqual(false, equal[1]); // 0.6km > 500m
-    try std.testing.expectEqual(true, equal[2]); // 0 == 0
-
-    // 3. Less than or equal
-    const low_eq = v1.lte(v3);
-    try std.testing.expect(low_eq[0] and low_eq[1] and low_eq[2]);
-}
-
-test "Vector vs Scalar Comparisons" {
-    const Meter = Scalar(f32, .{ .L = 1 }, .{});
-    const KiloMeter = Scalar(f32, .{ .L = 1 }, .{ .L = .k });
-
-    const positions = Meter.Vec3{ .data = .{ 500.0, 1200.0, 3000.0 } };
-    const threshold = KiloMeter{ .value = 1.0 }; // 1km (1000m)
-
-    // Check which axes exceed the 1km threshold
-    const exceeded = positions.gtScalar(threshold);
-
-    try std.testing.expectEqual(false, exceeded[0]); // 500m  > 1km is false
-    try std.testing.expectEqual(true, exceeded[1]); // 1200m > 1km is true
-    try std.testing.expectEqual(true, exceeded[2]); // 3000m > 1km is true
-
-    // Check for equality (broadcasted)
-    const exact_match = positions.eqScalar(Meter{ .value = 500.0 });
-    try std.testing.expect(exact_match[0] == true);
-    try std.testing.expect(exact_match[1] == false);
-}
-
-test "Vector Dot and Cross Products" {
-    const Meter = Scalar(f32, .{ .L = 1 }, .{});
-    const Newton = Scalar(f32, .{ .M = 1, .L = 1, .T = -2 }, .{});
-
-    const pos = Meter.Vec3{ .data = .{ 10.0, 0.0, 0.0 } };
-    const force = Newton.Vec3{ .data = .{ 5.0, 5.0, 0.0 } };
-
-    // 1. Dot Product (Work = F dot d)
-    const work = force.dot(pos);
-    try std.testing.expectEqual(50.0, work.value);
-    // Dimensions should be M¹L²T⁻² (Energy/Joules)
-    try std.testing.expectEqual(1, @TypeOf(work).dims.get(.M));
-    try std.testing.expectEqual(2, @TypeOf(work).dims.get(.L));
-    try std.testing.expectEqual(-2, @TypeOf(work).dims.get(.T));
-
-    // 2. Cross Product (Torque = r cross F)
-    const torque = pos.cross(force);
-    try std.testing.expectEqual(0.0, torque.data[0]);
-    try std.testing.expectEqual(0.0, torque.data[1]);
-    try std.testing.expectEqual(50.0, torque.data[2]);
-    // Torque dimensions are same as Energy but as a Vector
-    try std.testing.expectEqual(2, @TypeOf(torque).dims.get(.L));
-}
-
-test "Vector Abs, Pow, Sqrt and Product" {
-    const Meter = Scalar(f32, .{ .L = 1 }, .{});
-
-    const v1 = Meter.Vec3{ .data = .{ -2.0, 3.0, -4.0 } };
-
-    // 1. Abs
-    const v_abs = v1.abs();
-    try std.testing.expectEqual(2.0, v_abs.data[0]);
-    try std.testing.expectEqual(4.0, v_abs.data[2]);
-
-    // 2. Product (L1 * L1 * L1 = L3)
-    const vol = v_abs.product();
-    try std.testing.expectEqual(24.0, vol.value);
-    try std.testing.expectEqual(3, @TypeOf(vol).dims.get(.L));
-
-    // 3. Pow (Scalar exponent: (L1)^2 = L2)
-    const area_vec = v_abs.pow(2);
-    try std.testing.expectEqual(4.0, area_vec.data[0]);
-    try std.testing.expectEqual(16.0, area_vec.data[2]);
-    try std.testing.expectEqual(2, @TypeOf(area_vec).dims.get(.L));
-
-    // 4. Sqrt
-    const sqrted = area_vec.sqrt();
-    try std.testing.expectEqual(2, sqrted.data[0]);
-    try std.testing.expectEqual(4, sqrted.data[2]);
-    try std.testing.expectEqual(2, @TypeOf(sqrted).dims.get(.L));
-}
-
-test "mulScalar comptime_int" {
-    const Meter = Scalar(i32, .{ .L = 1 }, .{});
-    const v = Meter.Vec3{ .data = .{ 1, 2, 3 } };
-
-    const scaled = v.mulScalar(10); // comptime_int → dimensionless
-    try std.testing.expectEqual(10, scaled.data[0]);
-    try std.testing.expectEqual(20, scaled.data[1]);
-    try std.testing.expectEqual(30, scaled.data[2]);
-    // Dimensions unchanged: L¹ × dimensionless = L¹
-    try std.testing.expectEqual(1, @TypeOf(scaled).dims.get(.L));
-    try std.testing.expectEqual(0, @TypeOf(scaled).dims.get(.T));
-}
-
-test "mulScalar comptime_float" {
-    const MeterF = Scalar(f32, .{ .L = 1 }, .{});
-    const v = MeterF.Vec3{ .data = .{ 1.0, 2.0, 4.0 } };
-
-    const scaled = v.mulScalar(0.5); // comptime_float → dimensionless
-    try std.testing.expectApproxEqAbs(0.5, scaled.data[0], 1e-6);
-    try std.testing.expectApproxEqAbs(1.0, scaled.data[1], 1e-6);
-    try std.testing.expectApproxEqAbs(2.0, scaled.data[2], 1e-6);
-    try std.testing.expectEqual(1, @TypeOf(scaled).dims.get(.L));
-}
-
-test "mulScalar T (value type)" {
-    const MeterF = Scalar(f32, .{ .L = 1 }, .{});
-    const v = MeterF.Vec3{ .data = .{ 3.0, 6.0, 9.0 } };
-    const factor: f32 = 2.0;
-
-    const scaled = v.mulScalar(factor);
-    try std.testing.expectApproxEqAbs(6.0, scaled.data[0], 1e-6);
-    try std.testing.expectApproxEqAbs(12.0, scaled.data[1], 1e-6);
-    try std.testing.expectApproxEqAbs(18.0, scaled.data[2], 1e-6);
-    try std.testing.expectEqual(1, @TypeOf(scaled).dims.get(.L));
-}
-
-test "divScalar comptime_int" {
-    const Meter = Scalar(i32, .{ .L = 1 }, .{});
-    const v = Meter.Vec3{ .data = .{ 10, 20, 30 } };
-
-    const halved = v.divScalar(2); // comptime_int → dimensionless divisor
-    try std.testing.expectEqual(5, halved.data[0]);
-    try std.testing.expectEqual(10, halved.data[1]);
-    try std.testing.expectEqual(15, halved.data[2]);
-    try std.testing.expectEqual(1, @TypeOf(halved).dims.get(.L));
-}
-
-test "divScalar comptime_float" {
-    const MeterF = Scalar(f64, .{ .L = 1 }, .{});
-    const v = MeterF.Vec3{ .data = .{ 9.0, 6.0, 3.0 } };
-
-    const r = v.divScalar(3.0);
-    try std.testing.expectApproxEqAbs(3.0, r.data[0], 1e-9);
-    try std.testing.expectApproxEqAbs(2.0, r.data[1], 1e-9);
-    try std.testing.expectApproxEqAbs(1.0, r.data[2], 1e-9);
-    try std.testing.expectEqual(1, @TypeOf(r).dims.get(.L));
-}
-
-test "eqScalar / gtScalar with comptime_int on dimensionless vector" {
-    // Bare numbers are dimensionless, so comparisons only work when vector is dimensionless too.
-    const DimLess = Scalar(i32, .{}, .{});
-    const v = DimLess.Vec3{ .data = .{ 1, 2, 3 } };
-
-    const eq_res = v.eqScalar(2);
-    try std.testing.expectEqual(false, eq_res[0]);
-    try std.testing.expectEqual(true, eq_res[1]);
-    try std.testing.expectEqual(false, eq_res[2]);
-
-    const gt_res = v.gtScalar(1);
-    try std.testing.expectEqual(false, gt_res[0]);
-    try std.testing.expectEqual(true, gt_res[1]);
-    try std.testing.expectEqual(true, gt_res[2]);
-}

src/benchmark.zig

@@ -1,7 +1,6 @@
 const std = @import("std");
 const Io = std.Io;
-const Scalar = @import("Scalar.zig").Scalar;
-const Vector = @import("Vector.zig").Vector;
+const Tensor = @import("Tensor.zig").Tensor;
 
 var io: Io = undefined;
 pub fn main(init: std.process.Init) !void {
@@ -11,25 +10,12 @@ pub fn main(init: std.process.Init) !void {
 
     io = init.io;
 
-    try vectorSIMDvsNative(f64, &stdout_writer.interface);
+    try bench_Scalar(&stdout_writer.interface);
     try stdout_writer.flush();
-    try vectorSIMDvsNative(f32, &stdout_writer.interface);
+    try bench_Vector(&stdout_writer.interface);
     try stdout_writer.flush();
-    try vectorSIMDvsNative(i32, &stdout_writer.interface);
+    try bench_HighDimTensor(&stdout_writer.interface);
     try stdout_writer.flush();
-    try vectorSIMDvsNative(i64, &stdout_writer.interface);
-    try stdout_writer.flush();
-    try vectorSIMDvsNative(i128, &stdout_writer.interface);
-    try stdout_writer.flush();
-
-    // try bench_Scalar(&stdout_writer.interface);
-    // try stdout_writer.flush();
-    // try bench_vsNative(&stdout_writer.interface);
-    // try stdout_writer.flush();
-    // try bench_crossTypeVsNative(&stdout_writer.interface);
-    // try stdout_writer.flush();
-    // try bench_Vector(&stdout_writer.interface);
-    // try stdout_writer.flush();
 }
 
 fn getTime() Io.Timestamp {
@@ -97,9 +83,9 @@ fn bench_Scalar(writer: *std.Io.Writer) !void {
 
     comptime var tidx: usize = 0;
     inline for (Types, TNames) |T, tname| {
-        const M = Scalar(T, .{ .L = 1 }, .{});
-        const KM = Scalar(T, .{ .L = 1 }, .{ .L = .k });
-        const S = Scalar(T, .{ .T = 1 }, .{});
+        const M = Tensor(T, .{ .L = 1 }, .{}, &.{1});
+        const KM = Tensor(T, .{ .L = 1 }, .{ .L = .k }, &.{1});
+        const S = Tensor(T, .{ .T = 1 }, .{}, &.{1});
 
         inline for (Ops, 0..) |op_name, oidx| {
             var samples: [SAMPLES]f64 = undefined;
@@ -111,23 +97,23 @@ fn bench_Scalar(writer: *std.Io.Writer) !void {
                     std.mem.doNotOptimizeAway(
                         {
                             _ = if (comptime std.mem.eql(u8, op_name, "add"))
-                                (M{ .value = getVal(T, i, 63) }).add(M{ .value = getVal(T, i +% 7, 63) })
+                                (M.splat(getVal(T, i, 63))).add(M.splat(getVal(T, i +% 7, 63)))
                             else if (comptime std.mem.eql(u8, op_name, "sub"))
-                                (M{ .value = getVal(T, i +% 10, 63) }).sub(M{ .value = getVal(T, i, 63) })
+                                (M.splat(getVal(T, i +% 10, 63))).sub(M.splat(getVal(T, i, 63)))
                             else if (comptime std.mem.eql(u8, op_name, "mul"))
-                                (M{ .value = getVal(T, i, 63) }).mul(M{ .value = getVal(T, i +% 1, 63) })
+                                (M.splat(getVal(T, i, 63))).mul(M.splat(getVal(T, i +% 1, 63)))
                             else if (comptime std.mem.eql(u8, op_name, "div"))
-                                (M{ .value = getVal(T, i +% 10, 63) }).div(S{ .value = getVal(T, i, 63) })
+                                (M.splat(getVal(T, i +% 10, 63))).div(S.splat(getVal(T, i, 63)))
                             else if (comptime std.mem.eql(u8, op_name, "to"))
-                                (KM{ .value = getVal(T, i, 15) }).to(M)
+                                (KM.splat(getVal(T, i, 15))).to(M)
                             else if (comptime std.mem.eql(u8, op_name, "abs"))
-                                (M{ .value = getVal(T, i, 63) }).abs()
+                                (M.splat(getVal(T, i, 63))).abs()
                             else if (comptime std.mem.eql(u8, op_name, "eq"))
-                                (M{ .value = getVal(T, i, 63) }).eq(M{ .value = getVal(T, i +% 3, 63) })
+                                (M.splat(getVal(T, i, 63))).eq(M.splat(getVal(T, i +% 3, 63)))
                             else if (comptime std.mem.eql(u8, op_name, "gt"))
-                                (M{ .value = getVal(T, i, 63) }).gt(M{ .value = getVal(T, i +% 3, 63) })
+                                (M.splat(getVal(T, i, 63))).gt(M.splat(getVal(T, i +% 3, 63)))
                             else
-                                (M{ .value = getVal(T, i, 63) }).mul(3);
+                                (M.splat(getVal(T, i, 63))).mul(M.splat(3));
                         },
                     );
                 }
@@ -168,222 +154,6 @@ fn bench_Scalar(writer: *std.Io.Writer) !void {
     try writer.print("└──────────────┴───────┴───────┴───────┴───────┴───────┴───────┴───────┘\n", .{});
 }
 
-fn bench_vsNative(writer: *std.Io.Writer) !void {
-    const ITERS: usize = 100_000;
-    const SAMPLES: usize = 5;
-
-    const getValT = struct {
-        fn f(comptime TT: type, i: usize) TT {
-            const v = (i % 100) + 1;
-            return if (comptime @typeInfo(TT) == .float) @floatFromInt(v) else @intCast(v);
-        }
-    }.f;
-
-    const Types = .{ i32, i64, i128, f32, f64 };
-    const TNames = .{ "i32", "i64", "i128", "f32", "f64" };
-    // Expanded Ops to match bench_Scalar
-    const Ops = .{ "add", "sub", "mul", "div", "abs", "eq", "gt" };
-
-    try writer.print(
-        \\
-        \\ Scalar vs Native Overhead Analysis
-        \\
-        \\┌───────────┬──────┬───────────┬───────────┬───────────┐
-        \\│ Operation │ Type │ Native    │ Scalar    │ Slowdown  │
-        \\├───────────┼──────┼───────────┼───────────┼───────────┤
-        \\
-    , .{});
-
-    inline for (Ops, 0..) |op_name, j| {
-        inline for (Types, 0..) |T, tidx| {
-            var native_total_ns: f64 = 0;
-            var quantity_total_ns: f64 = 0;
-
-            const M = Scalar(T, .{ .L = 1 }, .{});
-            const S = Scalar(T, .{ .T = 1 }, .{});
-
-            std.mem.doNotOptimizeAway({
-                for (0..SAMPLES) |_| {
-                    // --- 1. Benchmark Native ---
-                    const n_start = getTime();
-                    for (0..ITERS) |i| {
-                        const a = getValT(T, i);
-                        const b = getValT(T, 2);
-
-                        // Native logic branch
-                        _ = if (comptime std.mem.eql(u8, op_name, "add"))
-                            a + b
-                        else if (comptime std.mem.eql(u8, op_name, "sub"))
-                            a - b
-                        else if (comptime std.mem.eql(u8, op_name, "mul"))
-                            a * b
-                        else if (comptime std.mem.eql(u8, op_name, "div"))
-                            if (comptime @typeInfo(T) == .int) @divTrunc(a, b) else a / b
-                        else if (comptime std.mem.eql(u8, op_name, "abs"))
-                            if (comptime @typeInfo(T) == .int) @abs(a) else @as(T, @abs(a))
-                        else if (comptime std.mem.eql(u8, op_name, "eq"))
-                            a == b
-                        else if (comptime std.mem.eql(u8, op_name, "gt"))
-                            a > b
-                        else
-                            unreachable;
-                    }
-                    const n_end = getTime();
-                    native_total_ns += @as(f64, @floatFromInt(n_start.durationTo(n_end).toNanoseconds()));
-
-                    // --- 2. Benchmark Scalar ---
-                    const q_start = getTime();
-                    for (0..ITERS) |i| {
-                        const qa = M{ .value = getValT(T, i) };
-                        const qb = if (comptime std.mem.eql(u8, op_name, "div")) S{ .value = getValT(T, 2) } else M{ .value = getValT(T, 2) };
-
-                        // Scalar logic branch
-                        _ = if (comptime std.mem.eql(u8, op_name, "add"))
-                            qa.add(qb)
-                        else if (comptime std.mem.eql(u8, op_name, "sub"))
-                            qa.sub(qb)
-                        else if (comptime std.mem.eql(u8, op_name, "mul"))
-                            qa.mul(qb)
-                        else if (comptime std.mem.eql(u8, op_name, "div"))
-                            qa.div(qb)
-                        else if (comptime std.mem.eql(u8, op_name, "abs"))
-                            qa.abs()
-                        else if (comptime std.mem.eql(u8, op_name, "eq"))
-                            qa.eq(qb)
-                        else if (comptime std.mem.eql(u8, op_name, "gt"))
-                            qa.gt(qb)
-                        else
-                            unreachable;
-                    }
-                    const q_end = getTime();
-                    quantity_total_ns += @as(f64, @floatFromInt(q_start.durationTo(q_end).toNanoseconds()));
-                }
-            });
-
-            const avg_n = (native_total_ns / SAMPLES) / @as(f64, @floatFromInt(ITERS));
-            const avg_q = (quantity_total_ns / SAMPLES) / @as(f64, @floatFromInt(ITERS));
-            const slowdown = avg_q / avg_n;
-
-            try writer.print("│ {s:<9} │ {s:<4} │ {d:>7.2}ns │ {d:>7.2}ns │ {d:>8.2}x │\n", .{
-                op_name, TNames[tidx], avg_n, avg_q, slowdown,
-            });
-        }
-        if (j != Ops.len - 1) try writer.print("├───────────┼──────┼───────────┼───────────┼───────────┤\n", .{});
-    }
-
-    try writer.print("└───────────┴──────┴───────────┴───────────┴───────────┘\n", .{});
-}
-
-fn bench_crossTypeVsNative(writer: *std.Io.Writer) !void {
-    const ITERS: usize = 100_000;
-    const SAMPLES: usize = 5;
-
-    const getValT = struct {
-        fn f(comptime TT: type, i: usize) TT {
-            // Keep values safe and non-zero to avoid division by zero or overflows during cross-casting
-            const v = (i % 50) + 1;
-            return if (comptime @typeInfo(TT) == .float) @floatFromInt(v) else @intCast(v);
-        }
-    }.f;
-
-    // Helper for the Native baseline: explicitly casting T2 to T1 before the operation
-    const castTo = struct {
-        fn f(comptime DestT: type, comptime SrcT: type, val: SrcT) DestT {
-            if (comptime DestT == SrcT) return val;
-            const src_info = @typeInfo(SrcT);
-            const dest_info = @typeInfo(DestT);
-
-            if (dest_info == .int and src_info == .int) return @intCast(val);
-            if (dest_info == .float and src_info == .int) return @floatFromInt(val);
-            if (dest_info == .int and src_info == .float) return @intFromFloat(val);
-            if (dest_info == .float and src_info == .float) return @floatCast(val);
-            unreachable;
-        }
-    }.f;
-
-    const Types = .{ i16, i64, i128, f32, f64 };
-    const TNames = .{ "i16", "i64", "i128", "f32", "f64" };
-    const Ops = .{ "add", "mul", "div" };
-
-    try writer.print(
-        \\
-        \\ Cross-Type Overhead Analysis: Scalar vs Native
-        \\
-        \\┌─────────┬──────┬──────┬───────────┬───────────┬───────────┐
-        \\│ Op      │ T1   │ T2   │ Native    │ Scalar    │ Slowdown  │
-        \\├─────────┼──────┼──────┼───────────┼───────────┼───────────┤
-        \\
-    , .{});
-
-    inline for (Ops, 0..) |op_name, j| {
-        inline for (Types, 0..) |T1, t1_idx| {
-            inline for (Types, 0..) |T2, t2_idx| {
-                var native_total_ns: f64 = 0;
-                var quantity_total_ns: f64 = 0;
-
-                const M1 = Scalar(T1, .{ .L = 1 }, .{});
-                const M2 = Scalar(T2, .{ .L = 1 }, .{});
-                const S2 = Scalar(T2, .{ .T = 1 }, .{});
-
-                std.mem.doNotOptimizeAway({
-                    for (0..SAMPLES) |_| {
-                        // --- 1. Benchmark Native (Cast T2 to T1, then math) ---
-                        const n_start = getTime();
-                        for (0..ITERS) |i| {
-                            const a = getValT(T1, i);
-                            const b_raw = getValT(T2, 2);
-                            const b = castTo(T1, T2, b_raw);
-
-                            _ = if (comptime std.mem.eql(u8, op_name, "add"))
-                                a + b
-                            else if (comptime std.mem.eql(u8, op_name, "mul"))
-                                a * b
-                            else if (comptime @typeInfo(T1) == .int)
-                                @divTrunc(a, b)
-                            else
-                                a / b;
-                        }
-                        const n_end = getTime();
-                        native_total_ns += @as(f64, @floatFromInt(n_start.durationTo(n_end).toNanoseconds()));
-
-                        // --- 2. Benchmark Scalar ---
-                        const q_start = getTime();
-                        for (0..ITERS) |i| {
-                            const qa = M1{ .value = getValT(T1, i) };
-                            const qb = if (comptime std.mem.eql(u8, op_name, "div"))
-                                S2{ .value = getValT(T2, 2) }
-                            else
-                                M2{ .value = getValT(T2, 2) };
-
-                            _ = if (comptime std.mem.eql(u8, op_name, "add"))
-                                qa.add(qb)
-                            else if (comptime std.mem.eql(u8, op_name, "mul"))
-                                qa.mul(qb)
-                            else
-                                qa.div(qb);
-                        }
-                        const q_end = getTime();
-                        quantity_total_ns += @as(f64, @floatFromInt(q_start.durationTo(q_end).toNanoseconds()));
-                    }
-
-                    const avg_n = (native_total_ns / SAMPLES) / @as(f64, @floatFromInt(ITERS));
-                    const avg_q = (quantity_total_ns / SAMPLES) / @as(f64, @floatFromInt(ITERS));
-                    const slowdown = avg_q / avg_n;
-
-                    try writer.print("│ {s:<7} │ {s:<4} │ {s:<4} │ {d:>7.2}ns │ {d:>7.2}ns │ {d:>8.2}x │\n", .{
-                        op_name, TNames[t1_idx], TNames[t2_idx], avg_n, avg_q, slowdown,
-                    });
-                });
-            }
-        }
-        if (j != Ops.len - 1) {
-            try writer.print("├─────────┼──────┼──────┼───────────┼───────────┼───────────┤\n", .{});
-        }
-    }
-
-    try writer.print("└─────────┴──────┴──────┴───────────┴───────────┴───────────┘\n", .{});
-}
-
 fn bench_Vector(writer: *std.Io.Writer) !void {
     const ITERS: usize = 10_000;
     const SAMPLES: usize = 10;
@@ -412,26 +182,25 @@ fn bench_Vector(writer: *std.Io.Writer) !void {
         \\ Vector<N, T> benchmark — {d} iterations, {d} samples/cell
         \\ (Results in ns/op; "---" = not applicable for this length)
         \\
-        \\┌──────────────────┬──────┬─────────┬─────────┬─────────┐
-        \\│ Operation        │ Type │   Len=3 │   Len=4 │  Len=16 │
-        \\├──────────────────┼──────┼─────────┼─────────┼─────────┤
+        \\┌──────────────────┬──────┬─────────┬─────────┬─────────┬─────────┬─────────┐
+        \\│ Operation        │ Type │   Len=1 │   Len=3 │   Len=4 │  Len=16 │ Len=100 │
+        \\├──────────────────┼──────┼─────────┼─────────┼─────────┼─────────┼─────────┤
         \\
     , .{ ITERS, SAMPLES });
 
     const Types = .{ i32, i64, i128, f32, f64 };
     const TNames = .{ "i32", "i64", "i128", "f32", "f64" };
-    const Lengths = .{ 3, 4, 16 };
+    const Lengths = .{ 1, 3, 4, 16, 100 };
     // "cross" is only valid for len=3; other cells will show "  ---  "
-    const Ops = .{ "add", "div", "mulScalar", "dot", "cross", "product", "pow", "length" };
+    const Ops = .{ "add", "div", "mulScalar", "dot", "product", "pow", "length" };
 
     inline for (Ops, 0..) |op_name, o_idx| {
         inline for (Types, TNames) |T, tname| {
             try writer.print("│ {s:<16} │ {s:<4} │", .{ op_name, tname });
 
             inline for (Lengths) |len| {
-                const Q_base = Scalar(T, .{ .L = 1 }, .{});
-                const Q_time = Scalar(T, .{ .T = 1 }, .{});
-                const V = Vector(len, Q_base);
+                const Q_time = Tensor(T, .{ .T = 1 }, .{}, &.{1});
+                const V = Tensor(T, .{ .L = 1 }, .{}, &.{len});
 
                 // cross product is only defined for len == 3
                 const is_cross = comptime std.mem.eql(u8, op_name, "cross");
@@ -446,23 +215,19 @@ fn bench_Vector(writer: *std.Io.Writer) !void {
                     for (0..SAMPLES) |s_idx| {
                         const t_start = getTime();
                         for (0..ITERS) |i| {
-                            const v1 = V.initDefault(getVal(T, i, 63));
+                            const v1 = V.splat(getVal(T, i, 63));
 
                             if (comptime std.mem.eql(u8, op_name, "add")) {
-                                const v2 = V.initDefault(getVal(T, i +% 7, 63));
+                                const v2 = V.splat(getVal(T, i +% 7, 63));
                                 _ = v1.add(v2);
                             } else if (comptime std.mem.eql(u8, op_name, "div")) {
-                                _ = v1.div(V.initDefault(getVal(T, i +% 2, 63)));
+                                _ = v1.div(V.splat(getVal(T, i +% 2, 63)));
                             } else if (comptime std.mem.eql(u8, op_name, "mulScalar")) {
-                                const s_val = Q_time{ .value = getVal(T, i +% 2, 63) };
-                                _ = v1.mulScalar(s_val);
+                                const s_val = Q_time.splat(getVal(T, i +% 2, 63));
+                                _ = v1.mul(s_val);
                             } else if (comptime std.mem.eql(u8, op_name, "dot")) {
-                                const v2 = V.initDefault(getVal(T, i +% 5, 63));
-                                _ = v1.dot(v2);
-                            } else if (comptime std.mem.eql(u8, op_name, "cross")) {
-                                // len == 3 guaranteed by the guard above
-                                const v2 = V.initDefault(getVal(T, i +% 5, 63));
-                                _ = v1.cross(v2);
+                                const v2 = V.splat(getVal(T, i +% 5, 63));
+                                _ = v1.contract(v2, 0, 0);
                             } else if (comptime std.mem.eql(u8, op_name, "product")) {
                                 _ = v1.product();
                             } else if (comptime std.mem.eql(u8, op_name, "pow")) {
@@ -484,67 +249,104 @@ fn bench_Vector(writer: *std.Io.Writer) !void {
         }
 
         if (o_idx < Ops.len - 1) {
-            try writer.print("├──────────────────┼──────┼─────────┼─────────┼─────────┤\n", .{});
+            try writer.print("├──────────────────┼──────┼─────────┼─────────┼─────────┼─────────┼─────────┤\n", .{});
         }
     }
-    try writer.print("└──────────────────┴──────┴─────────┴─────────┴─────────┘\n", .{});
+    try writer.print("└──────────────────┴──────┴─────────┴─────────┴─────────┴─────────┴─────────┘\n", .{});
 }
 
-fn vectorSIMDvsNative(comptime T: type, writer: *std.Io.Writer) !void {
-    const iterations: u64 = 10_000;
-    const lens = [_]u32{ 1, 2, 3, 4, 5, 10, 100, 1_000, 10_000 };
+fn bench_HighDimTensor(writer: *std.Io.Writer) !void {
+    const ITERS: usize = 5_000;
+    const SAMPLES: usize = 5;
 
-    try writer.print("\nSIMD Speedup Analysis: {s}\n", .{@typeName(T)});
-    try writer.print("┌────────────┬────────────┬────────────┬────────────┐\n", .{});
-    try writer.print("│ Vector Len │ Scalar (us)│ Vector (us)│ Speedup    │\n", .{});
-    try writer.print("├────────────┼────────────┼────────────┼────────────┤\n", .{});
-
-    inline for (lens) |vector_len| {
-        // --- Scalar Test ---
-        var scalar_val: T = 10;
-        const start_scalar = getTime();
-
-        var i: u64 = 0;
-        while (i < iterations * vector_len) : (i += 1) {
-            if (comptime @typeInfo(T) == .int)
-                scalar_val = scalar_val +% 1
-            else
-                scalar_val = scalar_val + 1;
+    const getVal = struct {
+        fn f(comptime TT: type, i: usize, comptime mask: u7) TT {
+            const v: u8 = @as(u8, @truncate(i & @as(usize, mask))) + 1;
+            return if (comptime @typeInfo(TT) == .float) @floatFromInt(v) else @intCast(v);
         }
-        const scalar_time = start_scalar.durationTo(getTime()).toMicroseconds();
+    }.f;
 
-        // --- Vector Test ---
-        var vector_val: @Vector(vector_len, T) = @splat(20);
-        const start_vector = getTime();
-
-        i = 0;
-        const increment: @Vector(vector_len, T) = @splat(1);
-        while (i < iterations) : (i += 1) {
-            if (comptime @typeInfo(T) == .int)
-                vector_val = vector_val +% increment
+    const computeStats = struct {
+        fn f(samples: []f64, iters: usize) f64 {
+            std.mem.sort(f64, samples, {}, std.sort.asc(f64));
+            const mid = samples.len / 2;
+            const median_ns = if (samples.len % 2 == 0)
+                (samples[mid - 1] + samples[mid]) / 2.0
             else
-                vector_val = vector_val + increment;
+                samples[mid];
+            return median_ns / @as(f64, @floatFromInt(iters));
         }
-        const vector_time = start_vector.durationTo(getTime()).toMicroseconds();
+    }.f;
 
-        // --- Results ---
-        const s_float = @as(f64, @floatFromInt(scalar_time));
-        const v_float = @as(f64, @floatFromInt(vector_time));
+    try writer.print(
+        \\
+        \\ High Dimension Tensor benchmark — {d} iterations, {d} samples/cell
+        \\ (Results in ns/op)
+        \\
+        \\┌─────────────────┬──────┬──────────────┬──────────────┬──────────────┬──────────────┐
+        \\│ Operation       │ Type │        2x2x2 │        3x3x3 │        4x4x4 │  10x10x10x10 │
+        \\├─────────────────┼──────┼──────────────┼──────────────┼──────────────┼──────────────┤
+        \\
+    , .{ ITERS, SAMPLES });
 
-        // Speedup = ScalarTime / VectorTime.
-        // > 1.0 means SIMD is faster.
-        const speedup = if (vector_time > 0) s_float / v_float else 0;
+    const Types = .{ i32, i64, f32, f64 };
+    const TNames = .{ "i32", "i64", "f32", "f64" };
 
-        try writer.print("│ {d:<10} │ {d:>10} │ {d:>10} │ {d:>9.2}x │\n", .{
-            vector_len,
-            scalar_time,
-            vector_time,
-            speedup,
+    // Testing multiple structural bounds
+    const Shapes = .{
+        &.{ 2, 2, 2 },
+        &.{ 3, 3, 3 },
+        &.{ 4, 4, 4 },
+        &.{ 10, 10, 10, 10 },
+    };
+
+    const Ops = .{ "add", "sub", "mulElem", "mulScalar", "abs" };
+
+    inline for (Ops, 0..) |op_name, o_idx| {
+        inline for (Types, TNames) |T, tname| {
+            try writer.print("│ {s:<15} │ {s:<4} │", .{ op_name, tname });
+
+            inline for (Shapes) |shape| {
+                const V = Tensor(T, .{ .L = 1 }, .{}, shape);
+                const Q = Tensor(T, .{ .T = 1 }, .{}, &.{1}); // For scalar broadcasting operations
+
+                var samples: [SAMPLES]f64 = undefined;
+
+                for (0..SAMPLES) |s_idx| {
+                    const t_start = getTime();
+
+                    for (0..ITERS) |i| {
+                        std.mem.doNotOptimizeAway({
+                            const t1 = V.splat(getVal(T, i, 63));
+
+                            _ = if (comptime std.mem.eql(u8, op_name, "add"))
+                                t1.add(V.splat(getVal(T, i +% 7, 63)))
+                            else if (comptime std.mem.eql(u8, op_name, "sub"))
+                                t1.sub(V.splat(getVal(T, i +% 3, 63)))
+                            else if (comptime std.mem.eql(u8, op_name, "mulElem"))
+                                t1.mul(V.splat(getVal(T, i +% 5, 63)))
+                            else if (comptime std.mem.eql(u8, op_name, "mulScalar"))
+                                t1.mul(Q.splat(getVal(T, i +% 2, 63)))
+                            else if (comptime std.mem.eql(u8, op_name, "abs"))
+                                t1.abs()
+                            else
+                                unreachable;
                         });
-        try writer.flush();
-
-        std.mem.doNotOptimizeAway(scalar_val);
-        std.mem.doNotOptimizeAway(vector_val);
                     }
-    try writer.print("└────────────┴────────────┴────────────┴────────────┘\n", .{});
+
+                    const t_end = getTime();
+                    samples[s_idx] = @as(f64, @floatFromInt(t_start.durationTo(t_end).toNanoseconds()));
+                }
+
+                const median_ns_per_op = computeStats(&samples, ITERS);
+                try writer.print(" {d:>12.1} │", .{median_ns_per_op});
+            }
+            try writer.print("\n", .{});
+        }
+
+        if (o_idx < Ops.len - 1) {
+            try writer.print("├─────────────────┼──────┼──────────────┼──────────────┼──────────────┼──────────────┤\n", .{});
+        }
+    }
+    try writer.print("└─────────────────┴──────┴──────────────┴──────────────┴──────────────┴──────────────┘\n", .{});
 }

src/helper.zig

@@ -1,98 +0,0 @@
-const std = @import("std");
-
-pub fn isInt(comptime T: type) bool {
-    return @typeInfo(T) == .int or @typeInfo(T) == .comptime_int;
-}
-
-pub fn printSuperscript(writer: *std.Io.Writer, n: i32) !void {
-    if (n == 0) return;
-    var val = n;
-    if (val < 0) {
-        try writer.writeAll("\u{207B}");
-        val = -val;
-    }
-    var buf: [12]u8 = undefined;
-    const str = std.fmt.bufPrint(&buf, "{d}", .{val}) catch return;
-    for (str) |c| {
-        const s = switch (c) {
-            '0' => "\u{2070}",
-            '1' => "\u{00B9}",
-            '2' => "\u{00B2}",
-            '3' => "\u{00B3}",
-            '4' => "\u{2074}",
-            '5' => "\u{2075}",
-            '6' => "\u{2076}",
-            '7' => "\u{2077}",
-            '8' => "\u{2078}",
-            '9' => "\u{2079}",
-            else => unreachable,
-        };
-        try writer.writeAll(s);
-    }
-}
-
-const Scales = @import("Scales.zig");
-const Dimensions = @import("Dimensions.zig");
-const Dimension = @import("Dimensions.zig").Dimension;
-
-pub fn finerScales(comptime T1: type, comptime T2: type) Scales {
-    const d1: Dimensions = T1.dims;
-    const d2: Dimensions = T2.dims;
-    const s1: Scales = T1.scales;
-    const s2: Scales = T2.scales;
-    comptime var out = Scales.initFill(.none);
-    inline for (std.enums.values(Dimension)) |dim| {
-        const scale1 = comptime s1.get(dim);
-        const scale2 = comptime s2.get(dim);
-        out.set(dim, if (comptime d1.get(dim) == 0 and d2.get(dim) == 0)
-            .none
-        else if (comptime d1.get(dim) == 0)
-            scale2
-        else if (comptime d2.get(dim) == 0)
-            scale1
-        else if (comptime scale1.getFactor() > scale2.getFactor())
-            scale2
-        else
-            scale1);
-    }
-    comptime return out;
-}
-
-// ---------------------------------------------------------------------------
-// RHS normalisation helpers
-// ---------------------------------------------------------------------------
-
-const Scalar = @import("Scalar.zig").Scalar;
-
-/// Returns true if `T` is a `Scalar_` type (has `dims`, `scales`, and `value`).
-pub fn isScalarType(comptime T: type) bool {
-    return @typeInfo(T) == .@"struct" and
-        @hasDecl(T, "dims") and
-        @hasDecl(T, "scales") and
-        @hasField(T, "value");
-}
-
-/// Resolve the Scalar type that `rhs` will be treated as.
-///
-/// Accepted rhs types:
-///   - Any `Scalar_` type               → returned as-is
-///   - `comptime_int` / `comptime_float` → dimensionless `Scalar_(BaseT, {}, {})`
-///   - `BaseT` (the scalar's value type) → dimensionless `Scalar_(BaseT, {}, {})`
-///
-/// Everything else is a compile error, including other int/float types.
-pub fn rhsScalarType(comptime BaseT: type, comptime RhsT: type) type {
-    if (comptime isScalarType(RhsT)) return RhsT;
-    if (comptime RhsT == comptime_int or RhsT == comptime_float or RhsT == BaseT)
-        return Scalar(BaseT, .{}, .{});
-    @compileError(
-        "rhs must be a Scalar, " ++ @typeName(BaseT) ++
-            ", comptime_int, or comptime_float; got " ++ @typeName(RhsT),
-    );
-}
-
-/// Convert `rhs` to its normalised Scalar form (see `rhsScalarType`).
-pub inline fn toRhsScalar(comptime BaseT: type, rhs: anytype) rhsScalarType(BaseT, @TypeOf(rhs)) {
-    if (comptime isScalarType(@TypeOf(rhs))) return rhs;
-    const DimLess = Scalar(BaseT, .{}, .{});
-    return DimLess{ .value = @as(BaseT, rhs) };
-}

src/lib.zig

@@ -0,0 +1,9 @@
+const std = @import("std");
+
+pub const TensorStatic = @import("TensorStatic.zig").Tensor;
+pub const TensorAlloc = @import("TensorAlloc.zig").Tensor;
+pub const TensorGpu = @import("TensorGpu.zig").Tensor;
+pub const Dimensions = @import("Dimensions.zig");
+pub const Scales = @import("Scales.zig");
+pub const Base = @import("Base.zig");
+pub const UnitParser = @import("UnitParser.zig");

src/main.zig

@@ -1,16 +0,0 @@
-const std = @import("std");
-
-pub const Scalar = @import("Scalar.zig").Scalar;
-pub const Vector = @import("Vector.zig").Vector;
-pub const Dimensions = @import("Dimensions.zig");
-pub const Scales = @import("Scales.zig");
-pub const Base = @import("Base.zig");
-
-test {
-    _ = @import("Quantity.zig");
-    // _ = @import("Vector.zig");
-    // _ = @import("Dimensions.zig");
-    // _ = @import("Scales.zig");
-    // _ = @import("Base.zig");
-    // _ = @import("helper.zig");
-}

src/shared.zig

@@ -0,0 +1,155 @@
+const std = @import("std");
+const Scales = @import("Scales.zig");
+const UnitScale = Scales.UnitScale;
+const Dimensions = @import("Dimensions.zig");
+const Dimension = Dimensions.Dimension;
+
+pub const TensorKind = enum { static, alloc, gpu };
+
+pub fn isTensor(comptime T: type) bool {
+    return comptime @typeInfo(T) == .@"struct" and @hasDecl(T, "ISTENSOR");
+}
+
+pub fn shapeTotal(shape: []const comptime_int) usize {
+    var t: comptime_int = 1;
+    for (shape) |s| t *= s;
+    return t;
+}
+
+/// Check if two shapes are strictly identical.
+pub fn shapeEql(a: []const comptime_int, b: []const comptime_int) bool {
+    if (a.len != b.len) return false;
+    for (a, 0..) |v, i|
+        if (v != b[i]) return false;
+    return true;
+}
+
+/// Row-major (C-order) strides: strides[i] = product(shape[i+1..]).
+///   e.g. shape {3, 4} → strides {4, 1}
+///        shape {2, 3, 4} → strides {12, 4, 1}
+pub fn shapeStrides(shape: []const comptime_int) [shape.len]comptime_int {
+    var st: [shape.len]comptime_int = undefined;
+    if (shape.len == 0) return st;
+    st[shape.len - 1] = 1;
+    if (shape.len > 1) {
+        var i: comptime_int = shape.len - 1;
+        while (i > 0) : (i -= 1) st[i - 1] = st[i] * shape[i];
+    }
+    return st;
+}
+
+/// Return a copy of `shape` with the element at `axis` removed.
+pub fn shapeRemoveAxis(shape: []const comptime_int, axis: comptime_int) [shape.len - 1]comptime_int {
+    var out: [shape.len - 1]comptime_int = undefined;
+    var j: comptime_int = 0;
+    for (shape, 0..) |v, i| {
+        if (i != axis) {
+            out[j] = v;
+            j += 1;
+        }
+    }
+    return out;
+}
+
+/// Concatenate two compile-time slices.
+pub fn shapeCat(a: []const comptime_int, b: []const comptime_int) [a.len + b.len]comptime_int {
+    var out: [a.len + b.len]comptime_int = undefined;
+    for (a, 0..) |v, i| out[i] = v;
+    for (b, 0..) |v, i| out[a.len + i] = v;
+    return out;
+}
+
+/// Decode a flat row-major index into N-D coordinates.
+/// Called only in comptime contexts (all arguments are comptime).
+pub fn decodeFlatCoords(flat: comptime_int, n: comptime_int, strd: [n]comptime_int) [n]usize {
+    var coords: [n]comptime_int = undefined;
+    var tmp = flat;
+    for (0..n) |i| {
+        coords[i] = if (strd[i] == 0) 0 else tmp / strd[i];
+        tmp = if (strd[i] == 0) 0 else tmp % strd[i];
+    }
+    return coords;
+}
+
+/// Encode N-D coordinates into a flat row-major index.
+/// Called only in comptime contexts.
+pub fn encodeFlatCoords(coords: []const usize, n: usize, strd: [n]usize) usize {
+    var flat: usize = 0;
+    for (0..n) |i| flat += coords[i] * strd[i];
+    return flat;
+}
+
+/// Rebuild a full coordinate array by inserting `val` at `axis` into `free`.
+/// `free` holds the remaining (non-contracted) coordinates in order.
+pub fn insertAxis(
+    comptime n: usize,
+    comptime axis: usize,
+    comptime val: usize,
+    comptime free: []const usize,
+) [n]usize {
+    var out: [n]usize = undefined;
+    var fi: usize = 0;
+    for (0..n) |i| {
+        if (i == axis) {
+            out[i] = val;
+        } else {
+            out[i] = free[fi];
+            fi += 1;
+        }
+    }
+    return out;
+}
+
+pub inline fn isInt(comptime T: type) bool {
+    return @typeInfo(T) == .int or @typeInfo(T) == .comptime_int;
+}
+
+pub fn finerScales(comptime T1: type, comptime T2: type) Scales {
+    const d1: Dimensions = T1.dims;
+    const d2: Dimensions = T2.dims;
+    const s1: Scales = T1.scales;
+    const s2: Scales = T2.scales;
+    comptime var out = Scales.initFill(.none);
+    for (std.enums.values(Dimension)) |dim| {
+        const scale1 = comptime s1.get(dim);
+        const scale2 = comptime s2.get(dim);
+        out.set(dim, if (comptime d1.get(dim) == 0 and d2.get(dim) == 0)
+            .none
+        else if (comptime d1.get(dim) == 0)
+            scale2
+        else if (comptime d2.get(dim) == 0)
+            scale1
+        else if (comptime scale1.getFactor() > scale2.getFactor())
+            scale2
+        else
+            scale1);
+    }
+    return out;
+}
+
+pub fn printSuperscript(writer: *std.Io.Writer, n: i32) !void {
+    if (n == 0) return;
+    var val = n;
+    if (val < 0) {
+        try writer.writeAll("\u{207B}");
+        val = -val;
+    }
+    var buf: [12]u8 = undefined;
+    const str = std.fmt.bufPrint(&buf, "{d}", .{val}) catch return;
+    for (str) |c| {
+        const s = switch (c) {
+            '0' => "\u{2070}",
+            '1' => "\u{00B9}",
+            '2' => "\u{00B2}",
+            '3' => "\u{00B3}",
+            '4' => "\u{2074}",
+            '5' => "\u{2075}",
+            '6' => "\u{2076}",
+            '7' => "\u{2077}",
+            '8' => "\u{2078}",
+            '9' => "\u{2079}",
+            else => unreachable,
+        };
+        try writer.writeAll(s);
+    }
+}

src/test.zig

@@ -0,0 +1,9 @@
+test {
+    _ = @import("TensorStatic.zig");
+    _ = @import("TensorAlloc.zig");
+    _ = @import("TensorGpu.zig");
+    _ = @import("Dimensions.zig");
+    _ = @import("Scales.zig");
+    _ = @import("Base.zig");
+    _ = @import("UnitParser.zig");
+}