main.js (1418B)
1 /** 2 * @license Apache-2.0 3 * 4 * Copyright (c) 2018 The Stdlib Authors. 5 * 6 * Licensed under the Apache License, Version 2.0 (the "License"); 7 * you may not use this file except in compliance with the License. 8 * You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, software 13 * distributed under the License is distributed on an "AS IS" BASIS, 14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 15 * See the License for the specific language governing permissions and 16 * limitations under the License. 17 */ 18 19 'use strict'; 20 21 // MODULES // 22 23 var factory = require( './factory.js' ); 24 25 26 // MAIN // 27 28 /** 29 * Returns a pseudorandom number drawn from a gamma distribution. 30 * 31 * ## References 32 * 33 * - Marsaglia, George, and Wai Wan Tsang. 2000. "A Simple Method for Generating Gamma Variables." _ACM Transactions on Mathematical Software_ 26 (3). New York, NY, USA: ACM: 363–72. doi:[10.1145/358407.358414](http://dx.doi.org/10.1145/358407.358414). 34 * 35 * 36 * @name gamma 37 * @type {PRNG} 38 * @param {PositiveNumber} alpha - shape parameter 39 * @param {PositiveNumber} beta - rate parameter 40 * @returns {PositiveNumber} pseudorandom number 41 * 42 * @example 43 * var v = gamma( 2.0, 4.0 ); 44 * // returns <number> 45 * 46 * @example 47 * var v = gamma( -2.0, 4.0 ); 48 * // returns NaN 49 */ 50 var gamma = factory(); 51 52 53 // EXPORTS // 54 55 module.exports = gamma;