time-to-botec/js/node_modules/@stdlib/stats/iter/stdev/lib/main.js

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/**
* @license Apache-2.0
*
* Copyright (c) 2019 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 isIteratorLike = require( '@stdlib/assert/is-iterator-like' );
var hasOwnProp = require( '@stdlib/assert/has-own-property' );
var isNumber = require( '@stdlib/assert/is-number' ).isPrimitive;
var incrstdev = require( './../../../incr/stdev' );
// MAIN //
/**
* Computes the corrected sample standard deviation over all iterated values.
*
* @param {Iterator} iterator - input iterator
* @param {number} [mean] - mean value
* @throws {TypeError} first argument must be an iterator
* @throws {TypeError} second argument must be a number
* @returns {(number|null)} corrected sample standard deviation
*
* @example
* var runif = require( '@stdlib/random/iter/uniform' );
*
* var rand = runif( -10.0, 10.0, {
* 'iter': 100
* });
*
* var s = iterstdev( rand );
* // returns <number>
*/
function iterstdev( iterator, mean ) {
var acc;
var v;
if ( !isIteratorLike( iterator ) ) {
throw new TypeError( 'invalid argument. First argument must be an iterator. Value: `'+iterator+'`.' );
}
if ( arguments.length > 1 ) {
if ( !isNumber( mean ) ) {
throw new TypeError( 'invalid argument. Second argument must be a number primitive. Value: `' + mean + '`.' );
}
acc = incrstdev( mean );
} else {
acc = incrstdev();
}
while ( true ) {
v = iterator.next();
if ( typeof v.value === 'number' ) {
acc( v.value );
} else if ( hasOwnProp( v, 'value' ) ) {
acc( NaN );
}
if ( v.done ) {
break;
}
}
return acc();
}
// EXPORTS //
module.exports = iterstdev;