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feat: implement lastIndexOf
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lib/node_modules/@stdlib/array/fixed-endian-factory/README.md

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// returns -1
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```
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<a name="method-last-index-of"></a>
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#### TypedArrayFE.prototype.lastIndexOf( searchElement\[, fromIndex] )
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Returns the last index at which a given element can be found in the array.
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```javascript
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var Float64ArrayFE = fixedEndianFactory( 'float64' );
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var arr = new Float64ArrayFE( 'little-endian', [ 1.0, 2.0, 3.0, 4.0, 2.0 ] );
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var idx = arr.lastIndexOf( 2.0 );
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// returns 4
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idx = arr.lastIndexOf( 2.0, 3 );
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// returns 1
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idx = arr.lastIndexOf( 2.0, -2 );
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// returns 1
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```
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If `searchElement` is not present in the array, the method returns `-1`.
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```javascript
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var Float64ArrayFE = fixedEndianFactory( 'float64' );
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var arr = new Float64ArrayFE( 'little-endian', [ 1.0, 2.0, 3.0, 4.0, 2.0 ] );
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var idx = arr.lastIndexOf( 5.0 );
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// returns -1
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```
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<a name="method-map"></a>
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#### TypedArray.prototype.map( callbackFn\[, thisArg] )
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/**
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* @license Apache-2.0
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*
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* Copyright (c) 2024 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 bench = require( '@stdlib/bench' );
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var isInteger = require( '@stdlib/assert/is-integer' ).isPrimitive;
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var factory = require( './../lib' );
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var pkg = require( './../package.json' ).name;
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// VARIABLES //
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var Float64ArrayFE = factory( 'float64' );
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// MAIN //
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bench( pkg+':lastIndexOf', function benchmark( b ) {
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var arr;
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var idx;
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var i;
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arr = new Float64ArrayFE( 'little-endian', [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0 ] );
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b.tic();
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for ( i = 0; i < b.iterations; i++ ) {
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idx = arr.lastIndexOf( 5.0, arr.length - 1 );
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if ( typeof idx !== 'number' ) {
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b.fail( 'should return an integer' );
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}
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}
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b.toc();
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if ( !isInteger( idx ) ) {
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b.fail( 'should return an integer' );
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}
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b.pass( 'benchmark finished' );
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b.end();
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});
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/**
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* @license Apache-2.0
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*
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* Copyright (c) 2024 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 bench = require( '@stdlib/bench' );
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var pow = require( '@stdlib/math/base/special/pow' );
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var zeroTo = require( '@stdlib/array/zero-to' );
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var isInteger = require( '@stdlib/assert/is-integer' ).isPrimitive;
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var factory = require( './../lib' );
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var pkg = require( './../package.json' ).name;
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// VARIABLES //
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var Float64ArrayFE = factory( 'float64' );
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// FUNCTIONS //
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/**
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* Creates a benchmark function.
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*
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* @private
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* @param {PositiveInteger} len - array length
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* @returns {Function} benchmark function
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*/
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function createBenchmark( len ) {
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var arr = new Float64ArrayFE( 'little-endian', zeroTo( len ) );
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return benchmark;
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/**
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* Benchmark function.
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*
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* @private
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* @param {Benchmark} b - benchmark instance
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*/
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function benchmark( b ) {
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var idx;
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var v;
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var i;
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v = len - 1;
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b.tic();
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for ( i = 0; i < b.iterations; i++ ) {
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idx = arr.lastIndexOf( v );
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if ( typeof idx !== 'number' ) {
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b.fail( 'should return an integer' );
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}
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}
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b.toc();
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if ( !isInteger( idx ) ) {
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b.fail( 'should return an integer' );
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}
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b.pass( 'benchmark finished' );
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b.end();
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}
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}
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// MAIN //
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/**
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* Main execution sequence.
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*
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* @private
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*/
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function main() {
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var len;
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var min;
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var max;
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var f;
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var i;
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min = 1; // 10^min
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max = 6; // 10^max
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for ( i = min; i <= max; i++ ) {
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len = pow( 10, i );
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f = createBenchmark( len );
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bench( pkg+':lastIndexOf:len='+len, f );
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}
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}
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main();

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