time-to-botec/js/node_modules/@stdlib/stats/base/smskmax/lib/ndarray.native.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 Float32Array = require( '@stdlib/array/float32' );
var Uint8Array = require( '@stdlib/array/uint8' );
var addon = require( './smskmax.native.js' );
// MAIN //
/**
* Computes the maximum value of a single-precision floating-point strided array according to a mask.
*
* @param {PositiveInteger} N - number of indexed elements
* @param {Float32Array} x - input array
* @param {integer} strideX - `x` stride length
* @param {NonNegativeInteger} offsetX - `x` starting index
* @param {Uint8Array} mask - mask array
* @param {integer} strideMask - `mask` stride length
* @param {NonNegativeInteger} offsetMask - `mask` starting index
* @returns {number} maximum value
*
* @example
* var Float32Array = require( '@stdlib/array/float32' );
* var Uint8Array = require( '@stdlib/array/uint8' );
* 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, 5.0, 6.0 ] );
* var mask = new Uint8Array( [ 0, 0, 0, 0, 0, 0, 0, 0, 1, 1 ] );
* var N = floor( x.length / 2 );
*
* var v = smskmax( N, x, 2, 1, mask, 2, 1 );
* // returns 4.0
*/
function smskmax( N, x, strideX, offsetX, mask, strideMask, offsetMask ) {
var viewX;
var viewM;
if ( strideX < 0 ) {
offsetX += (N-1) * strideX;
}
if ( strideMask < 0 ) {
offsetMask += (N-1) * strideMask;
}
viewX = new Float32Array( x.buffer, x.byteOffset+(x.BYTES_PER_ELEMENT*offsetX), x.length-offsetX ); // eslint-disable-line max-len
viewM = new Uint8Array( mask.buffer, mask.byteOffset+(mask.BYTES_PER_ELEMENT*offsetMask), mask.length-offsetMask ); // eslint-disable-line max-len
return addon( N, viewX, strideX, viewM, strideMask );
}
// EXPORTS //
module.exports = smskmax;