splat-ecs/lib/random.js

A 2D HTML5 Canvas game engine

/** @module splat-ecs/lib/random */

module.exports = {
  /**
   * Get a pseudo-random number between the minimum (inclusive) and maximum (exclusive) parameters.
   * @function inRange
   * @param {number} min Inclusive minimum value for the random number
   * @param {number} max Exclusive maximum value for the random number
   * @returns {number} A number between <code>min</code> and <code>max</code>
   * @see [Bracket Notation: Inclusion and Exclusion]{@link https://en.wikipedia.org/wiki/Bracket_%28mathematics%29#Intervals}
   * @example
var random = require("splat-ecs/lib/random");
random.inRange(0, 1) // Returns 0.345822917402371
random.inRange(10, 100) // Returns 42.4823819274931274
   */
  "inRange": function(min, max) {
    return min + Math.random() * (max - min);
  },

  /**
   * Get a random element in an array
   * @function from
   * @param {array} array Array of elements to choose from
   * @returns {Object} A random element from the given array
   * @example
var random = require("splat-ecs/lib/random");
var fruit = ["Apple", "Banana", "Orange", "Peach"];
random.from(fruit); // Could return "Orange"
random.from(fruit); // Could return "Apple"
random.from(fruit); // Could return "Peach"
random.from(fruit); // Could return "Banana"
   */
  "from": function(array) {
    return array[Math.floor(Math.random() * array.length)];
  }
};