time-to-botec/js/node_modules/@stdlib/stats/base/snanstdevwd/lib/ndarray.js

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/**
* @license Apache-2.0
*
* Copyright (c) 2020 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 float64ToFloat32 = require( '@stdlib/number/float64/base/to-float32' );
var snanvariancewd = require( './../../../base/snanvariancewd' ).ndarray;
var sqrt = require( '@stdlib/math/base/special/sqrt' );
// MAIN //
/**
* Computes the standard deviation of a single-precision floating-point strided array ignoring `NaN` values and using Welford's algorithm.
*
* @param {PositiveInteger} N - number of indexed elements
* @param {number} correction - degrees of freedom adjustment
* @param {Float32Array} x - input array
* @param {integer} stride - stride length
* @param {NonNegativeInteger} offset - starting index
* @returns {number} standard deviation
*
* @example
* var Float32Array = require( '@stdlib/array/float32' );
* var floor = require( '@stdlib/math/base/special/floor' );
*
* var x = new Float32Array( [ 2.0, 1.0, 2.0, -2.0, -2.0, 2.0, 3.0, 4.0, NaN, NaN ] );
* var N = floor( x.length / 2 );
*
* var v = snanstdevwd( N, 1, x, 2, 1 );
* // returns 2.5
*/
function snanstdevwd( N, correction, x, stride, offset ) {
return float64ToFloat32( sqrt( snanvariancewd( N, correction, x, stride, offset ) ) ); // eslint-disable-line max-len
}
// EXPORTS //
module.exports = snanstdevwd;