time-to-botec/js/node_modules/@stdlib/stats/incr/mmeanabs/lib/main.js
NunoSempere b6addc7f05 feat: add the node modules
Necessary in order to clearly see the squiggle hotwiring.
2022-12-03 12:44:49 +00:00

85 lines
2.0 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 isPositiveInteger = require( '@stdlib/assert/is-positive-integer' ).isPrimitive;
var abs = require( '@stdlib/math/base/special/abs' );
var incrmmean = require( './../../../incr/mmean' );
// MAIN //
/**
* Returns an accumulator function which incrementally computes a moving arithmetic mean of absolute values.
*
* @param {PositiveInteger} W - window size
* @throws {TypeError} must provide a positive integer
* @returns {Function} accumulator function
*
* @example
* var accumulator = incrmmeanabs( 3 );
*
* var mu = accumulator();
* // returns null
*
* mu = accumulator( 2.0 );
* // returns 2.0
*
* mu = accumulator( -5.0 );
* // returns 3.5
*
* mu = accumulator( 3.0 );
* // returns ~3.33
*
* mu = accumulator( 5.0 );
* // returns ~4.33
*
* mu = accumulator();
* // returns ~4.33
*/
function incrmmeanabs( W ) {
var mean;
if ( !isPositiveInteger( W ) ) {
throw new TypeError( 'invalid argument. Must provide a positive integer. Value: `' + W + '`.' );
}
mean = incrmmean( W );
return accumulator;
/**
* If provided a value, the accumulator function returns an updated mean. If not provided a value, the accumulator function returns the current mean.
*
* @private
* @param {number} [x] - input value
* @returns {(number|null)} mean or null
*/
function accumulator( x ) {
if ( arguments.length === 0 ) {
return mean();
}
return mean( abs( x ) );
}
}
// EXPORTS //
module.exports = incrmmeanabs;