numwasm

NumPy-inspired n-dimensional array operations in TypeScript, with performance-critical operations compiled to WebAssembly.

Documentation & Demos | npm

Features

• NumPy-compatible API — familiar function names and semantics (zeros, ones, linspace, matmul, fft, mean, reshape, ...)
• WebAssembly acceleration — BLAS, LAPACK, FFT, sorting, statistics, and random number generation implemented in C and compiled to WASM
• Full TypeScript types — complete type definitions with documented parameters
• Dual module support — ESM and CommonJS, works in Node.js and browsers
• 600+ functions across linear algebra, FFT, statistics, random, polynomials, string operations, masked arrays, and more

Installation

npm install numjs-wasm

Quick Start

import {
  loadWasmModule,
  array,
  zeros,
  ones,
  linspace,
  reshape,
  add,
  matmul,
  mean,
} from "numjs-wasm";

// Initialize the WASM module (required once before use)
await loadWasmModule();

// Create arrays
const a = array([1, 2, 3, 4, 5, 6]);
const b = zeros([3, 3]);
const c = ones([2, 3]);
const d = linspace(0, 1, 100);

// Reshape and compute
const matrix = reshape(a, [2, 3]);
const result = add(matrix, c);
const product = await matmul(reshape(a, [2, 3]), reshape(a, [3, 2]));

// Statistics
const avg = mean(d);

Modules

Linear Algebra (linalg)

import { linalg } from "numjs-wasm";

const result = await linalg.matmul(a, b);
const { values, vectors } = await linalg.eig(matrix);
const solution = await linalg.solve(coefficients, constants);
const determinant = await linalg.det(matrix);

matmul, dot, inv, det, solve, eig, eigh, svd, qr, cholesky, norm, cond, lstsq, matrix_rank, matrix_power, cross, kron, tensordot, ...

FFT

import { fftModule } from "numjs-wasm";

const spectrum = fftModule.fft(signal);
const freqs = fftModule.fftfreq(n, dt);

fft, ifft, rfft, irfft, fft2, ifft2, fftn, ifftn, fftfreq, rfftfreq, fftshift, ifftshift, hfft, ihfft

Random

import { default_rng, Generator } from "numjs-wasm";

const rng = default_rng(42);
const samples = rng.normal(0, 1, [1000]);
const uniform = rng.uniform(0, 1, [100]);

Bit generators: PCG64, MT19937, Philox, SFC64. Distributions: normal, uniform, exponential, gamma, beta, binomial, poisson, and 20+ more.

Masked Arrays (ma)

import { ma } from "numjs-wasm";

const masked = ma.array(data, { mask: [false, false, true, false] });
const avg = ma.average(masked);

Polynomials

import { Polynomial, Chebyshev } from "numjs-wasm";

const p = new Polynomial([1, 2, 3]); // 1 + 2x + 3x^2
const roots = p.roots();

Polynomial, Chebyshev, Legendre, Hermite, HermiteE, Laguerre with full arithmetic, fitting, roots, and conversions.

Other Modules

• Strings (strings) — element-wise string operations on arrays
• Record Arrays (rec) — structured/tabular data with named fields
• Testing (testing) — assert_allclose, assert_array_equal, assert_raises, ...

Core API

| Category | Functions | | ------------------ | ------------------------------------------------------------------------------------------------------------------------------------ | | Array Creation | array, zeros, ones, empty, full, arange, linspace, logspace, geomspace, eye, identity, diag, meshgrid, ... | | Manipulation | reshape, transpose, concatenate, stack, split, flip, roll, rot90, tile, repeat, pad, ... | | Math | add, subtract, multiply, divide, power, sqrt, exp, log, sin, cos, tan, abs, clip, ... | | Statistics | mean, median, std, var_, min, max, sum, prod, histogram, percentile, quantile, ... | | Sorting | sort, argsort, argmax, argmin, searchsorted, partition, ... | | Logic | all, any, where, logical_and, logical_or, logical_not, ... | | Comparison | equal, greater, less, allclose, isclose, isnan, isinf, ... | | Set Operations | unique, union1d, intersect1d, setdiff1d, isin, ... | | I/O | save, load, loadtxt, savetxt, genfromtxt, frombuffer, ... | | Constants | pi, e, inf, nan, euler_gamma, newaxis |

AI / LLM Access

The documentation site serves machine-readable files following the llms.txt convention:

• llms.txt — project overview with module links
• llms-full.txt — complete API reference (all 600+ functions with signatures and descriptions)

MCP Server

The numwasm-mcp package provides a Model Context Protocol server that gives AI coding assistants searchable access to the full API docs. It ships with a bundled docs index — no network calls at runtime.

Tools exposed:

• search_numwasm_docs — search by function name, module, category, or keyword
• list_numwasm_modules — list all modules and categories

Claude Desktop — add to claude_desktop_config.json:

{
  "mcpServers": {
    "numwasm-docs": {
      "command": "npx",
      "args": ["-y", "numwasm-mcp"]
    }
  }
}

Claude Code — add .mcp.json to your project root:

{
  "mcpServers": {
    "numwasm-docs": {
      "command": "npx",
      "args": ["-y", "numwasm-mcp"]
    }
  }
}

Development

Prerequisites

• Node.js >= 18
• pnpm
• Emscripten (for building WASM from C sources)
• Python 3 + NumPy (for generating test fixtures and running comparison benchmarks)

Build

# Install dependencies
pnpm install

# Build WASM + TypeScript library
npm run build

# Or step by step:
npm run build:wasm    # Compile C → WebAssembly
npm run build:lib     # Bundle TypeScript with Vite

Test

# Run all tests
npm test

# Watch mode
npm run test:watch

# Run comparison tests against NumPy reference vectors
npm run test:compare

# Browser tests (Playwright)
npm run test:browser

Benchmark

# Full benchmark pipeline (build + NumPy + NumJS + report)
npm run benchmark

# Individual steps
npm run benchmark:numpy
npm run benchmark:numjs
npm run benchmark:combine

Documentation Site

# Generate TypeDoc JSON
npm run docs

# Dev server
npm run dev:docs

# Full static build (SSG + sitemap + llms.txt)
cd docs-site && pnpm run build:ssg

Project Structure

src/
  ts/              TypeScript implementation (NDArray, ufuncs, modules)
  wasm/            C source files compiled to WebAssembly
scripts/
  build-wasm.sh    Emscripten build script
tests/
  ts/              Vitest unit & integration tests
  browser/         Playwright browser tests
  python/          NumPy test fixture generators
benchmark/
  ts/              TypeScript benchmark suites
  python/          NumPy comparison benchmarks
docs-site/         React + Vite documentation website
dist/              Build output (library + WASM binary)

License

MIT