All files prng.js

83.33% Statements 75/90
33.33% Branches 2/6
100% Functions 1/1
83.33% Lines 75/90

Press n or j to go to the next uncovered block, b, p or k for the previous block.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 913x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 3x 12x 12x 12x 12x 12x     12x 12x     12x 12x 12x 12x 12x                 12x       12x 12x 3x 3x 3x 3x 3x  
/**
* @license Apache-2.0
*
* Copyright (c) 2026 The Stdlib Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
*    http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
 
'use strict';
 
// MODULES //
 
var discreteUniform = require( '@stdlib/random/base/discrete-uniform' ).factory;
var uniform = require( '@stdlib/random/base/uniform' ).factory;
var hasOwnProp = require( '@stdlib/assert/has-own-property' );
var isObject = require( '@stdlib/assert/is-plain-object' );
var isFunction = require( '@stdlib/assert/is-function' );
var format = require( '@stdlib/string/format' );
var FLOAT64_EPS = require( '@stdlib/constants/float64/eps' );
var INT32_MAX = require( '@stdlib/constants/int32/max' );
 
 
// MAIN //
 
/**
* Returns pseudorandom number generators for performing k-means++ initialization.
*
* ## Notes
*
* -   The returned array contains the following pseudorandom number generators:
*
*     -   **0**: a function for generating uniformly distributed pseudorandom integers on a closed interval.
*     -   **1**: a function for generating uniformly distributed pseudorandom numbers on the half-open interval `[0,1)`.
*
* @private
* @param {boolean} hasOptions - boolean indicating whether to process an options argument
* @param {Options} [options] - function options
* @param {PRNG} [options.prng] - pseudorandom number generator which generates uniformly distributed pseudorandom numbers
* @param {PRNGSeedMT19937} [options.seed] - pseudorandom number generator seed
* @param {PRNGStateMT19937} [options.state] - pseudorandom number generator state
* @param {boolean} [options.copy=true] - boolean indicating whether to copy a provided pseudorandom number generator state
* @throws {TypeError} options argument must be an object
* @throws {TypeError} options.prng must be a pseudorandom number generator function
* @returns {Array<Function>} array of pseudorandom number generators
*/
function prng( hasOptions, options ) {
	var randi;
	var rand;
	if ( hasOptions ) {
		if ( !isObject( options ) ) {
			throw new TypeError( format( 'invalid argument. Options argument must be an object. Value: `%s`.', options ) );
		}
		if ( hasOwnProp( options, 'prng' ) ) {
			if ( !isFunction( options.prng ) ) {
				throw new TypeError( format( 'invalid option. `%s` option must be a pseudorandom number generator function. Option: `%s`.', 'prng', options.prng ) );
			}
			randi = discreteUniform( options );
			rand = uniform( 0.0, 1.0-FLOAT64_EPS, {
				'prng': options.prng.normalized
			});
		} else if ( hasOwnProp( options, 'seed' ) ) {
			randi = discreteUniform( options );
			rand = uniform( 0.0, 1.0-FLOAT64_EPS, {
				'seed': randi( 1, INT32_MAX )
			});
		} else {
			randi = discreteUniform( options );
			rand = uniform( 0.0, 1.0-FLOAT64_EPS, options );
		}
	} else {
		randi = discreteUniform();
		rand = uniform( 0.0, 1.0-FLOAT64_EPS );
	}
	return [ randi, rand ];
}
 
 
// EXPORTS //
 
module.exports = prng;