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Add implementation for generic interface to compute the absolute value
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‎lib/node_modules/@stdlib/math/special/abs/examples/index.js

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/**
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* @license Apache-2.0
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*
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* Copyright (c) 2020 The Stdlib Authors.
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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'use strict';
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var Float64Array = require( '@stdlib/array/float64' );
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var array = require( '@stdlib/ndarray/array' );
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var ind2sub = require( '@stdlib/ndarray/ind2sub' );
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var abs = require( './../lib' );
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var sub;
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var sh;
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var x;
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var y;
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var i;
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// Provide a number...
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y = abs( -1.0 );
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console.log( 'x = %d => abs(x) = %d', -1.0, y );
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// Provide an array-like object...
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x = new Float64Array( [ -1.0, -2.0, -3.0 ] );
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y = abs( x );
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for ( i = 0; i < x.length; i++ ) {
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console.log( 'x_%d = %d => abs(x_%d) = %d', i, x[ i ], i, y.iget( i ) );
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}
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// Provide an ndarray...
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x = array( [ [ -1.0, -2.0 ], [ -3.0, -4.0 ] ] );
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sh = x.shape;
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y = abs( x );
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for ( i = 0; i < x.length; i++ ) {
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sub = ind2sub( sh, i );
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console.log( 'x_%d%d = %d => abs(x_%d%d) = %d', sub[ 0 ], sub[ 1 ], x.iget( i ), sub[ 0 ], sub[ 1 ], y.iget( i ) );
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}

‎lib/node_modules/@stdlib/math/special/abs/lib/index.js

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/**
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* @license Apache-2.0
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*
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* Copyright (c) 2020 The Stdlib Authors.
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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'use strict';
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/**
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* Compute the absolute value.
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*
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* @module @stdlib/math/special/abs
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*
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* @example
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* var abs = require( '@stdlib/math/special/abs' );
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*
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* var y = abs( -1.0 );
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* // returns 1.0
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*
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* @example
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* var Float64Array = require( '@stdlib/array/float64' );
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* var abs = require( '@stdlib/math/special/abs' );
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*
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* var x = new Float64Array( [ 1.0, -1.0, 0.0 ] );
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*
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* var y = abs( x );
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* // returns <Float64Array>[ 1.0, 1.0, 0.0 ]
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*
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* @example
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* var array = require( '@stdlib/ndarray/array' );
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* var abs = require( '@stdlib/math/special/abs' );
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*
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* var x = array( [ [ 1.0, -2.0 ], [ -3.0, 4.0 ] ] );
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* // returns <ndarray>
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*
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* var y = abs( x );
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* // returns <ndarray>
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*
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* var v = y.get( 0, 1 );
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* // 2.0
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*/
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// MAIN //
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var main = require( './main.js' );
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// EXPORTS //
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module.exports = main;

‎lib/node_modules/@stdlib/math/special/abs/lib/main.js

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/**
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* @license Apache-2.0
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*
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* Copyright (c) 2020 The Stdlib Authors.
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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'use strict';
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// MODULES //
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var isNumber = require( '@stdlib/assert/is-number' ).isPrimitive;
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var isndarrayLike = require( '@stdlib/assert/is-ndarray-like' );
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var isArrayLikeObject = require( '@stdlib/assert/is-array-like-object' );
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var isSingleSegmentCompatible = require( '@stdlib/ndarray/base/assert/is-single-segment-compatible' );
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var isFloat64Array = require( '@stdlib/assert/is-float64array' );
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var isFloat32Array = require( '@stdlib/assert/is-float32array' );
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var ndarray = require( '@stdlib/ndarray/ctor' );
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var buffer = require( '@stdlib/ndarray/base/buffer' );
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var shape2strides = require( '@stdlib/ndarray/base/shape2strides' );
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var iterationOrder = require( '@stdlib/ndarray/base/iteration-order' );
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var dtype = require( '@stdlib/ndarray/base/buffer-dtype' );
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var base = require( '@stdlib/math/base/special/abs' );
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var dabs = require( '@stdlib/math/strided/special/dabs' );
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var sabs = require( '@stdlib/math/strided/special/sabs' );
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var gabs = require( '@stdlib/math/strided/special/abs' );
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// MAIN //
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/**
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* Computes the absolute value.
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*
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* @param {(ndarray|ArrayLikeObject|number)} x - input value
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* @param {(ndarray|ArrayLikeObject)} [mask] - array mask
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* @throws {TypeError} first argument must be either an ndarray, array-like object, or number
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* @throws {TypeError} second argument must be either an ndarray or array-like object
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* @throws {Error} second argument must have the same shape as the first argument
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* @returns {(ndarray|number)} results
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*
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* @example
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* var y = abs( -1.0 );
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* // returns 1.0
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*
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* @example
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* var Float64Array = require( '@stdlib/array/float64' );
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*
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* var x = new Float64Array( [ 1.0, -1.0, 0.0 ] );
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*
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* var y = abs( x );
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* // returns <ndarray>
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*
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* var d = y.data;
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* // returns <Float64Array>[ 1.0, 1.0, 0.0 ]
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*
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* @example
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* var array = require( '@stdlib/ndarray/array' );
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*
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* var x = array( [ [ 1.0, -2.0 ], [ -3.0, 4.0 ] ] );
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* // returns <ndarray>
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*
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* var y = abs( x );
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* // returns <ndarray>
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*
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* var v = y.get( 0, 1 );
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* // 2.0
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*/
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function abs( x ) {
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var strides;
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var offset;
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var order;
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var ndims;
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var shape;
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var data;
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var ctor;
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var buf;
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var xc;
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var dt;
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var N;
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var s;
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var y;
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var i;
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if ( isNumber( x ) ) {
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return base( x );
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}
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// TODO: add complex number support; should probably coincide with complex number array support
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if ( isndarrayLike( x ) ) {
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// Cache ndarray properties to avoid repeatedly calling ndarray accessors...
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N = x.length;
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ndims = x.ndims;
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shape = x.shape;
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strides = x.strides;
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offset = x.offset;
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order = x.order;
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data = x.data;
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dt = x.dtype;
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// Create an output ndarray...
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ctor = ndarray( dt, ndims );
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buf = buffer( dt, N );
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y = ctor( buf, shape, shape2strides( shape, order ), 0, order );
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// Determine whether we can use one-dimensional type-optimized implementations...
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if ( ndims === 1 ) {
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if ( dt === 'float64' ) {
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dabs.ndarray( N, data, strides[ 0 ], offset, buf, 1, 0 );
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} else if ( dt === 'float32' ) {
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sabs.ndarray( N, data, strides[ 0 ], offset, buf, 1, 0 );
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} else {
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gabs.ndarray( N, data, strides[ 0 ], offset, buf, 1, 0 );
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}
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return y;
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}
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// Determine whether we can ignore shape (and strides) and treat `x` as a linear array...
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s = iterationOrder( strides ); // +/-1
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if ( s !== 0 && isSingleSegmentCompatible( shape, strides, offset ) ) { // Note: equivalent to @stdlib/ndarray/base/assert/is-contiguous, but in-lined so we can retain iteration order
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if ( dt === 'float64' ) {
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dabs.ndarray( N, data, s, offset, buf, 1, 0 );
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} else if ( dt === 'float32' ) {
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sabs.ndarray( N, data, s, offset, buf, 1, 0 );
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} else {
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gabs.ndarray( N, data, s, offset, buf, 1, 0 );
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}
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return y;
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}
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// At this point, `x` is a non-contiguous n-dimensional array, so we cannot directly use lower-level strided array functionality...
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// TODO: consider cache oblivious iteration, rather than data copy...
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xc = buffer( dt, N );
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for ( i = 0; i < N; i++ ) {
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xc[ i ] = x.iget( i );
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}
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// The buffer copy is contiguous so we can now use lower-level strided array functionality...
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if ( dt === 'float64' ) {
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dabs( N, xc, 1, buf, 1 );
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} else if ( dt === 'float32' ) {
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sabs( N, xc, 1, buf, 1 );
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} else {
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gabs( N, xc, 1, buf, 1 );
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}
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return y;
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}
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if ( !isArrayLikeObject( x ) ) {
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throw new TypeError( 'invalid argument. First argument must be either a number, array-like object, or ndarray. Value: `' + x + '`.' );
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}
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N = x.length;
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dt = dtype( x ) || 'generic';
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// Create an output array...
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ctor = ndarray( dt, 1 );
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buf = buffer( dt, N );
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y = ctor( buf, [ N ], [ 1 ], 0, 'row-major' );
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if ( isFloat64Array( x ) ) {
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dabs( x.length, x, 1, buf, 1 );
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} else if ( isFloat32Array( x ) ) {
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sabs( x.length, x, 1, buf, 1 );
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} else {
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gabs( x.length, x, 1, buf, 1 );
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}
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return y;
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}
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// EXPORTS //
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module.exports = abs;

‎lib/node_modules/@stdlib/math/special/abs/package.json

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{
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"name": "@stdlib/math/special/abs",
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"version": "0.0.0",
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"description": "Compute the absolute value.",
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"license": "Apache-2.0",
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"author": {
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"name": "The Stdlib Authors",
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"url": "https://github.com/stdlib-js/stdlib/graphs/contributors"
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},
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"contributors": [
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{
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"name": "The Stdlib Authors",
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"url": "https://github.com/stdlib-js/stdlib/graphs/contributors"
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}
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],
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"main": "./lib",
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"directories": {
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"benchmark": "./benchmark",
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"doc": "./docs",
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"example": "./examples",
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"lib": "./lib",
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"test": "./test"
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},
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"types": "./docs/types",
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"scripts": {},
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"homepage": "https://github.com/stdlib-js/stdlib",
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"repository": {
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"type": "git",
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"url": "git://github.com/stdlib-js/stdlib.git"
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},
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"bugs": {
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"url": "https://github.com/stdlib-js/stdlib/issues"
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},
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"dependencies": {},
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"devDependencies": {},
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"engines": {
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"node": ">=0.10.0",
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"npm": ">2.7.0"
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},
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"os": [
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"aix",
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"darwin",
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"freebsd",
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"linux",
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"macos",
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"openbsd",
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"sunos",
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"win32",
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"windows"
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],
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"keywords": [
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"stdlib",
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"stdmath",
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"mathematics",
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"math",
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"math.abs",
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"abs",
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"absolute",
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"magnitude",
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"value"
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],
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"__stdlib__": {}
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}

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