highs

highs-js

This is a javascript linear programming library. It is built by compiling HiGHS to WebAssembly using emscripten.

Usage

const highs = await require("highs")();

const PROBLEM = `Maximize
 obj: x1 + 2 x2 + 3 x3 + x4
Subject To
 c1: - x1 + x2 + x3 + 10 x4 <= 20
 c2: x1 - 3 x2 + x3 <= 30
 c3: x2 - 3.5 x4 = 0
Bounds
 0 <= x1 <= 40
 2 <= x4 <= 3
End`;

const sol = Module.solve(PROBLEM);

assert.deepEqual(sol, {
  Columns: {
    x1: {
      Index: 0,
      Status: 'UB',
      Lower: 0,
      Upper: 40,
      Primal: 40,
      Dual: 1.29167,
      Name: 'x1'
    },
    x2: {
      Index: 1,
      Status: 'BS',
      Lower: 0,
      Upper: Infinity,
      Primal: 10.2083,
      Dual: -0,
      Name: 'x2'
    },
    x3: {
      Index: 2,
      Status: 'BS',
      Lower: 0,
      Upper: Infinity,
      Primal: 20.625,
      Dual: -0,
      Name: 'x3'
    },
    x4: {
      Index: 3,
      Status: 'BS',
      Lower: 2,
      Upper: 3,
      Primal: 2.91667,
      Dual: -0,
      Name: 'x4'
    }
  },
  Rows: [
    {
      Index: 0,
      Status: 'UB',
      Lower: -Infinity,
      Upper: 20,
      Primal: 20,
      Dual: -1.64583
    },
    {
      Index: 1,
      Status: 'UB',
      Lower: -Infinity,
      Upper: 30,
      Primal: 30,
      Dual: -1.35417
    },
    {
      Index: 2,
      Status: 'FX',
      Lower: 0,
      Upper: 0,
      Primal: 0,
      Dual: -4.41667
    }
  ]
});

Loading the wasm file

This package requires a wasm file. You can find it in node_modules/highs/build/highs.wasm inside the NPM package, or download it from the release page. By default, it will be loaded from the same path as the javascript file, which mean you have to add the wasm file to your assets.

Alternatively, if you don't want to bother with that, you can load the file directly from github:

const highs_loader = require("highs");

const highs = await highs_loader({
  locateFile: (file) => "https://lovasoa.github.io/highs-js/" + file
});

Demo

See the online demo at: https://lovasoa.github.io/highs-js/