60 lines
1.6 KiB
JavaScript
60 lines
1.6 KiB
JavaScript
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/**
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* @license Apache-2.0
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*
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* Copyright (c) 2018 The Stdlib Authors.
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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'use strict';
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// MODULES //
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var factory = require( './factory.js' );
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// MAIN //
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/**
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* Generates a binomially distributed random number.
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*
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* ## Method
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*
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* - For \\(np < 10\\), the function generates Bernoulli random variates and returns their sum.
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* - For \\(np \geq 10\\), the function uses the [BTRD algorithm][@hormann:1993a].
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*
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* ## References
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*
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* - Hörmann, Wolfgang. 1993. "The generation of binomial random variates." _Journal of Statistical Computation and Simulation_ 46 (1-2): 101–10. doi:[10.1080/00949659308811496][@hormann:1993a].
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*
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* [@hormann:1993a]: http://dx.doi.org/10.1080/00949659308811496
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*
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* @name binomial
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* @type {PRNG}
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* @param {PositiveInteger} n - number of trials
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* @param {Probability} p - success probability
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* @throws {TypeError} `n` must be a positive integer
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* @throws {TypeError} `p` must be a probability
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* @returns {NonNegativeInteger} pseudorandom number
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*
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* @example
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* var r = binomial( 20, 0.8 );
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* // returns <number>
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*/
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var binomial = factory();
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// EXPORTS //
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module.exports = binomial;
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