mathjs/lib/function/probability/random.js

Math.js is an extensive math library for JavaScript and Node.js. It features a flexible expression parser and offers an integrated solution to work with numbers, big numbers, complex numbers, units, and matrices.

'use strict';

module.exports = function (math) {
  var distribution = require('./distribution')(math);

  /**
   * Return a random number larger or equal to `min` and smaller than `max`
   * using a uniform distribution.
   *
   * Syntax:
   *
   *     math.random()                // generate a random number between 0 and 1
   *     math.random(max)             // generate a random number between 0 and max
   *     math.random(min, max)        // generate a random number between min and max
   *     math.random(size)            // generate a matrix with random numbers between 0 and 1
   *     math.random(size, max)       // generate a matrix with random numbers between 0 and max
   *     math.random(size, min, max)  // generate a matrix with random numbers between min and max
   *
   * Examples:
   *
   *     math.random();       // returns a random number between 0 and 1
   *     math.random(100);    // returns a random number between 0 and 100
   *     math.random(30, 40); // returns a random number between 30 and 40
   *     math.random([2, 3]); // returns a 2x3 matrix with random numbers between 0 and 1
   *
   * See also:
   *
   *     randomInt, pickRandom
   *
   * @param {Array | Matrix} [size] If provided, an array or matrix with given
   *                                size and filled with random values is returned
   * @param {Number} [min]  Minimum boundary for the random value, included
   * @param {Number} [max]  Maximum boundary for the random value, excluded
   * @return {Number | Array | Matrix} A random number
   */
  math.random = distribution('uniform').random;
};