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 | 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 3019x 3019x 3019x 3019x 3019x 3004x 3019x 18x 18x 3001x 3001x 3001x 3001x 3001x 3001x 3001x 3001x 3001x 3001x 3001x 3001x 3001x 3001x 3002x 3002x 2x 2x 3000x 3000x 3002x 3019x 3x 3x 3x 3x 3x | /**
* @license Apache-2.0
*
* Copyright (c) 2018 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 constantFunction = require( '@stdlib/utils/constant-function' );
var kernelBetaincinv = require( '@stdlib/math/base/special/kernel-betaincinv' );
var isnan = require( '@stdlib/math/base/assert/is-nan' );
// MAIN //
/**
* Returns a function for evaluating the quantile function for an F distribution with numerator degrees of freedom `d1` and denominator degrees of freedom `d2`.
*
* @param {PositiveNumber} d1 - numerator degrees of freedom
* @param {PositiveNumber} d2 - denominator degrees of freedom
* @returns {Function} quantile function
*
* @example
* var quantile = factory( 10.0, 2.0 );
* var y = quantile( 0.4 );
* // returns ~0.994
*
* y = quantile( 0.8 );
* // returns ~4.382
*/
function factory( d1, d2 ) {
if (
isnan( d1 ) ||
isnan( d2 ) ||
d1 <= 0.0 ||
d2 <= 0.0
) {
return constantFunction( NaN );
}
return quantile;
/**
* Evaluates the quantile function for an F distribution.
*
* @private
* @param {Probability} p - input value
* @returns {number} evaluated quantile function
*
* @example
* var y = quantile( 0.3 );
* // returns <number>
*/
function quantile( p ) {
var xs;
if ( isnan( p ) || p < 0.0 || p > 1.0 ) {
return NaN;
}
xs = kernelBetaincinv( d1/2.0, d2/2.0, p, 1.0 - p );
return d2 * xs[ 0 ] / ( d1 * xs[ 1 ] );
}
}
// EXPORTS //
module.exports = factory;
|