time-to-botec/squiggle/node_modules/@stdlib/strided/base/smskmap/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';
// MAIN //
/**
* Applies a unary function accepting and returning single-precision floating-point numbers to each element in a single-precision floating-point strided input array according to a corresponding element in a strided mask array and assigns each result to an element in a single-precision floating-point strided output array.
*
* @param {NonNegativeInteger} N - number of indexed elements
* @param {Float32Array} x - input array
* @param {integer} strideX - `x` stride length
* @param {NonNegativeInteger} offsetX - starting `x` index
* @param {Uint8Array} mask - mask array
* @param {integer} strideMask - `mask` stride length
* @param {NonNegativeInteger} offsetMask - starting `mask` index
* @param {Float32Array} y - destination array
* @param {integer} strideY - `y` stride length
* @param {NonNegativeInteger} offsetY - starting `y` index
* @param {Function} fcn - unary function to apply
* @returns {Float32Array} `y`
*
* @example
* var Float32Array = require( '@stdlib/array/float32' );
* var Uint8Array = require( '@stdlib/array/uint8' );
*
* function scale( x ) {
* return x * 10.0;
* }
*
* var x = new Float32Array( [ 1.0, 2.0, 3.0, 4.0, 5.0 ] );
* var m = new Uint8Array( [ 0, 0, 1, 0, 0 ] );
* var y = new Float32Array( x.length );
*
* smskmap( x.length, x, 1, 0, m, 1, 0, y, 1, 0, scale );
*
* console.log( y );
* // => <Float32Array>[ 10.0, 20.0, 0.0, 40.0, 50.0 ]
*/
function smskmap( N, x, strideX, offsetX, mask, strideMask, offsetMask, y, strideY, offsetY, fcn ) { // eslint-disable-line max-len, max-params
var ix;
var im;
var iy;
var i;
if ( N <= 0 ) {
return y;
}
ix = offsetX;
im = offsetMask;
iy = offsetY;
for ( i = 0; i < N; i++ ) {
if ( mask[ im ] === 0 ) {
y[ iy ] = fcn( x[ ix ] );
}
ix += strideX;
im += strideMask;
iy += strideY;
}
return y;
}
// EXPORTS //
module.exports = smskmap;