40 lines
1.1 KiB
JavaScript
40 lines
1.1 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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/**
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* Returns a pseudorandom number from an F distribution with parameters `d1` and `d2`.
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*
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* @private
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* @param {PRNG} rchisq - PRNG for chi-square distributed numbers
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* @param {PositiveNumber} d1 - degrees of freedom
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* @param {PositiveNumber} d2 - degrees of freedom
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* @returns {NonNegativeNumber} pseudorandom number
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*/
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function f( rchisq, d1, d2 ) {
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var x1 = rchisq( d1 ) / d1;
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var x2 = rchisq( d2 ) / d2;
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return x1 / x2;
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}
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// EXPORTS //
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module.exports = f;
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