simple-squiggle

A restricted subset of Squiggle
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random.js (3527B)


      1 import { factory } from '../../utils/factory.js';
      2 import { isMatrix } from '../../utils/is.js';
      3 import { createRng } from './util/seededRNG.js';
      4 import { randomMatrix } from './util/randomMatrix.js';
      5 var name = 'random';
      6 var dependencies = ['typed', 'config', '?on'];
      7 export var createRandom = /* #__PURE__ */factory(name, dependencies, _ref => {
      8   var {
      9     typed,
     10     config,
     11     on
     12   } = _ref;
     13   // seeded pseudo random number generator
     14   var rng = createRng(config.randomSeed);
     15 
     16   if (on) {
     17     on('config', function (curr, prev) {
     18       if (curr.randomSeed !== prev.randomSeed) {
     19         rng = createRng(curr.randomSeed);
     20       }
     21     });
     22   }
     23   /**
     24    * Return a random number larger or equal to `min` and smaller than `max`
     25    * using a uniform distribution.
     26    *
     27    * Syntax:
     28    *
     29    *     math.random()                // generate a random number between 0 and 1
     30    *     math.random(max)             // generate a random number between 0 and max
     31    *     math.random(min, max)        // generate a random number between min and max
     32    *     math.random(size)            // generate a matrix with random numbers between 0 and 1
     33    *     math.random(size, max)       // generate a matrix with random numbers between 0 and max
     34    *     math.random(size, min, max)  // generate a matrix with random numbers between min and max
     35    *
     36    * Examples:
     37    *
     38    *     math.random()       // returns a random number between 0 and 1
     39    *     math.random(100)    // returns a random number between 0 and 100
     40    *     math.random(30, 40) // returns a random number between 30 and 40
     41    *     math.random([2, 3]) // returns a 2x3 matrix with random numbers between 0 and 1
     42    *
     43    * See also:
     44    *
     45    *     randomInt, pickRandom
     46    *
     47    * @param {Array | Matrix} [size] If provided, an array or matrix with given
     48    *                                size and filled with random values is returned
     49    * @param {number} [min]  Minimum boundary for the random value, included
     50    * @param {number} [max]  Maximum boundary for the random value, excluded
     51    * @return {number | Array | Matrix} A random number
     52    */
     53 
     54 
     55   return typed(name, {
     56     '': () => _random(0, 1),
     57     number: max => _random(0, max),
     58     'number, number': (min, max) => _random(min, max),
     59     'Array | Matrix': size => _randomMatrix(size, 0, 1),
     60     'Array | Matrix, number': (size, max) => _randomMatrix(size, 0, max),
     61     'Array | Matrix, number, number': (size, min, max) => _randomMatrix(size, min, max)
     62   });
     63 
     64   function _randomMatrix(size, min, max) {
     65     var res = randomMatrix(size.valueOf(), () => _random(min, max));
     66     return isMatrix(size) ? size.create(res) : res;
     67   }
     68 
     69   function _random(min, max) {
     70     return min + rng() * (max - min);
     71   }
     72 }); // number only implementation of random, no matrix support
     73 // TODO: there is quite some duplicate code in both createRandom and createRandomNumber, can we improve that?
     74 
     75 export var createRandomNumber = /* #__PURE__ */factory(name, ['typed', 'config', '?on'], _ref2 => {
     76   var {
     77     typed,
     78     config,
     79     on,
     80     matrix
     81   } = _ref2;
     82   // seeded pseudo random number generator1
     83   var rng = createRng(config.randomSeed);
     84 
     85   if (on) {
     86     on('config', function (curr, prev) {
     87       if (curr.randomSeed !== prev.randomSeed) {
     88         rng = createRng(curr.randomSeed);
     89       }
     90     });
     91   }
     92 
     93   return typed(name, {
     94     '': () => _random(0, 1),
     95     number: max => _random(0, max),
     96     'number, number': (min, max) => _random(min, max)
     97   });
     98 
     99   function _random(min, max) {
    100     return min + rng() * (max - min);
    101   }
    102 });