nj

np in js

Installation

via npm

npm i @irreg/nj

Minified bundle file for browser use

Get started

Once installed, you can use it in both ES6 module and CommonJS formats or in browser.

ES6 module (recommended)

import * as nj from '@irreg/nj';

CommonJS

const nj = require('@irreg/nj');

In browser

<script src="./bundle.min.cjs"></script>
<script>
    console.log(nj.arange(10));
</script>

API

Indexing

let a = nj.arange(10).at(nj.slice(5));
console.log(a); // array([5, 6, 7, 8, 9])
a = nj.arange(10).at(nj.slice(5, 0, -1));
console.log(a); // array([5, 4, 3, 2, 1])
a = nj.arange(10).at(':5').at('::-1');
console.log(a); // array([4, 3, 2, 1, 0])
a = nj.arange(10).at(nj.slice(5), null);
console.log(a); // array([[5], [6], [7], [8], [9]])

Basic Indexing and view

let a = nj.arange(9).reshape(-1, 3);
let b = a.at(':', 0);
console.log(b); // array([0, 3, 6])
b.fill(-1);
console.log(b); // array([-1, -1, -1])
console.log(a); // array([[-1, 1, 2], [-1, 4, 5], [-1, 7, 8]])

Advanced indexing and set

let a = nj.arange(9).reshape(-1, 3);
let mask = nj.greater(a, 5);
console.log(mask); // array([[false, false, false], [false, false, false], [true, true, true]])
let b = a.at(mask);
console.log(b); // array([6, 7, 8])
a.set([mask], -1);
console.log(a); // array([[0, 1, 2], [3, 4, 5], [-1, -1, -1]])

Broadcasting

let a = nj.arange(9).reshape(-1, 3);
a = nj.add(a, [1, 2, 3]);
console.log(a); // array([[1, 3, 5], [4, 6, 8], [7, 9, 11]]

Numerics

let a = nj.array([
	[1, 2, 3],
	[4, 5, 6],
]);
console.log(nj.cumsum(a)); // array([1, 3, 6, 10, 15, 21])

console.log(nj.sum([[0, 1], [0, 5]], 0)); // array([0, 6])
console.log(nj.sum([[0, 1], [0, 5]], 1)); // array([1, 5])

Flatten

let a = nj.arange(9).reshape(-1, 3);
a.set([[0, -1], 1], -1);
console.log(a.flatten()); // array([0, -1, 2, 3, 4, 5, 6, -1, 8])

It does most of what you expected with numpy.

Documentation

To find more documentation on the APIs, you can visit https://zgtcktom.github.io/nj/ (generated by jsdoc).

Both jsdoc comments and .d.mts typescript declaration files are available. Recommend using VSCode for code editing.

Build from git

git clone https://github.com/zgtcktom/nj.git
npm install
npm run build