52 lines
1.2 KiB
JavaScript
52 lines
1.2 KiB
JavaScript
/**
|
|
* @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 sample1 = require( './sample1.js' );
|
|
var sample2 = require( './sample2.js' );
|
|
|
|
|
|
// MAIN //
|
|
|
|
/**
|
|
* Returns a pseudorandom number drawn from a binomial distribution.
|
|
*
|
|
* @private
|
|
* @param {PRNG} rand - PRNG for uniformly distributed numbers
|
|
* @param {PositiveInteger} n - number of trials
|
|
* @param {Probability} p - probability of success
|
|
* @returns {NonNegativeInteger} pseudorandom number
|
|
*/
|
|
function sample( rand, n, p ) {
|
|
if ( p > 0.5 ) {
|
|
return n - sample( rand, n, 1.0-p );
|
|
}
|
|
if ( n*p < 10.0 ) {
|
|
return sample1( rand, n, p );
|
|
}
|
|
return sample2( rand, n, p );
|
|
}
|
|
|
|
|
|
// EXPORTS //
|
|
|
|
module.exports = sample;
|