feat: add map method to array/fixed-endian-factory

PR-URL: #3270
Closes: #3150
Co-authored-by: Athan Reines <kgryte@gmail.com>
Reviewed-by: Athan Reines <kgryte@gmail.com>

Author: aayush0325

lib/node_modules/@stdlib/array/fixed-endian-factory/README.md

@@ -483,6 +483,68 @@ var v = arr.get( 100 );
 // returns undefined
 ```
 
+<a name="method-map"></a>
+
+#### TypedArray.prototype.map( callbackFn\[, thisArg] )
+
+Returns a new array with each element being the result of a provided callback function.
+
+```javascript
+function fcn( v ) {
+    return -v;
+}
+
+var Float64ArrayFE = fixedEndianFactory( 'float64' );
+
+var arr = new Float64ArrayFE( 'little-endian', [ 1.0, 2.0, 3.0 ] );
+// returns <Float64ArrayFE>
+
+var out = arr.map( fcn );
+// returns <Float64ArrayFE>
+
+var z = out.get( 0 );
+// returns -1.0
+
+z = out.get( 1 );
+// returns -2.0
+
+z = out.get( 2 );
+// returns -3.0
+```
+
+The callback function is provided three arguments:
+
+-   **value**: current array element.
+-   **index**: current array element index.
+-   **arr**: the array on which this method was called.
+
+To set the function execution context, provide a `thisArg`.
+
+```javascript
+function fcn( v, i ) {
+    this.count += i;
+    return -v;
+}
+
+var Float64ArrayFE = fixedEndianFactory( 'float64' );
+
+var arr = new Float64ArrayFE( 'little-endian', 3 );
+
+arr.set( -1.0, 0 );
+arr.set( 1.0, 1 );
+arr.set( -1.0, 2 );
+
+var context = {
+    'count': 0
+};
+
+var out = arr.map( fcn, context );
+// returns <Float64ArrayFE>
+
+var count = context.count;
+// returns 3;
+```
+
 <a name="method-set"></a>
 
 #### TypedArrayFE.prototype.set( arr\[, offset] )

lib/node_modules/@stdlib/array/fixed-endian-factory/benchmark/benchmark.map.js

@@ -0,0 +1,59 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2024 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 bench = require( '@stdlib/bench' );
+var pkg = require( './../package.json' ).name;
+var factory = require( './../lib' );
+
+
+// VARIABLES //
+
+var Float64ArrayFE = factory( 'float64' );
+
+
+// MAIN //
+
+bench( pkg+':map', function benchmark( b ) {
+	var out;
+	var arr;
+	var i;
+
+	arr = new Float64ArrayFE( 'little-endian', [ 1.0, 2.0, 2.0, 1.0 ] );
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		out = arr.map( identity );
+		if ( typeof out !== 'object' ) {
+			b.fail( 'should return an object' );
+		}
+	}
+	b.toc();
+	if ( !( out instanceof Float64ArrayFE ) ) {
+		b.fail( 'should return a typed array' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+
+	function identity( v ) {
+		return v;
+	}
+});

lib/node_modules/@stdlib/array/fixed-endian-factory/benchmark/benchmark.map.length.js

@@ -0,0 +1,112 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2024 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 bench = require( '@stdlib/bench' );
+var pow = require( '@stdlib/math/base/special/pow' );
+var zeroTo = require( '@stdlib/array/zero-to' );
+var pkg = require( './../package.json' ).name;
+var factory = require( './../lib' );
+
+
+// VARIABLES //
+
+var Float64ArrayFE = factory( 'float64' );
+
+
+// FUNCTIONS //
+
+/**
+* Identity function.
+*
+* @private
+* @param {number} value - array element
+* @param {NonNegativeInteger} idx - array element index
+* @param {TypedArray} arr - array instance
+* @returns {number} input array element
+*/
+function identity( value ) {
+	return value;
+}
+
+/**
+* Creates a benchmark function.
+*
+* @private
+* @param {PositiveInteger} len - array length
+* @returns {Function} benchmark function
+*/
+function createBenchmark( len ) {
+	var arr = new Float64ArrayFE( 'little-endian', zeroTo( len ) );
+	return benchmark;
+
+	/**
+	* Benchmark function.
+	*
+	* @private
+	* @param {Benchmark} b - benchmark instance
+	*/
+	function benchmark( b ) {
+		var out;
+		var i;
+
+		b.tic();
+		for ( i = 0; i < b.iterations; i++ ) {
+			out = arr.map( identity );
+			if ( typeof out !== 'object' ) {
+				b.fail( 'should return an object' );
+			}
+		}
+		b.toc();
+		if ( !( out instanceof Float64ArrayFE ) ) {
+			b.fail( 'should return a TypedArray' );
+		}
+		b.pass( 'benchmark finished' );
+		b.end();
+	}
+}
+
+
+// MAIN //
+
+/**
+* Main execution sequence.
+*
+* @private
+*/
+function main() {
+	var len;
+	var min;
+	var max;
+	var f;
+	var i;
+
+	min = 1; // 10^min
+	max = 6; // 10^max
+
+	for ( i = min; i <= max; i++ ) {
+		len = pow( 10, i );
+		f = createBenchmark( len );
+		bench( pkg+':map:len='+len, f );
+	}
+}
+
+main();

lib/node_modules/@stdlib/array/fixed-endian-factory/lib/main.js

@@ -51,6 +51,8 @@ var fromIteratorMap = require( './from_iterator_map.js' );
 // VARIABLES //
 
 var HAS_ITERATOR_SYMBOL = hasIteratorSymbolSupport();
+var LITTLE_ENDIAN = 'little-endian';
+var BIG_ENDIAN = 'big-endian';
 var DTYPES = [ 'float64', 'float32', 'int32', 'int16', 'uint32', 'uint16' ];
 var DTYPE2SET = {
 	'float64': 'setFloat64',
@@ -99,7 +101,18 @@ function byteOrder( value ) {
 * @returns {boolean} boolean indicating whether a byte order is little-endian byte order
 */
 function isLittleEndian( value ) {
-	return ( value === 'little-endian' );
+	return ( value === LITTLE_ENDIAN );
+}
+
+/**
+* Resolves a byte order string from a boolean flag.
+*
+* @private
+* @param {boolean} isLE - flag indicating whether an array is little-endian
+* @returns {string} resolved byte order
+*/
+function flag2byteOrder( isLE ) {
+	return ( isLE ) ? LITTLE_ENDIAN : BIG_ENDIAN;
 }
 
 /**
@@ -634,6 +647,41 @@ function factory( dtype ) { // eslint-disable-line max-lines-per-function, stdli
 		return this._length;
 	});
 
+	/**
+	* Returns a new array with each element being the result of a provided callback function.
+	*
+	* @private
+	* @name map
+	* @memberof TypedArray.prototype
+	* @type {Function}
+	* @param {Function} fcn - function to invoke
+	* @param {*} [thisArg] - function invocation context
+	* @throws {TypeError} `this` must be a typed array instance
+	* @throws {TypeError} first argument must be a function
+	* @returns {TypedArray} new typed array
+	*/
+	setReadOnly( TypedArray.prototype, 'map', function map( fcn, thisArg ) {
+		var obuf;
+		var out;
+		var buf;
+		var i;
+		var v;
+		if ( !isTypedArray( this ) ) {
+			throw new TypeError( format( 'invalid invocation. `this` is not %s %s.', CHAR2ARTICLE[ dtype[0] ], CTOR_NAME ) );
+		}
+		if ( !isFunction( fcn ) ) {
+			throw new TypeError( format( 'invalid argument. First argument must be a function. Value: `%s`.', fcn ) );
+		}
+		buf = this._buffer;
+		out = new this.constructor( flag2byteOrder( this._isLE ), this._length );
+		obuf = out._buffer; // eslint-disable-line no-underscore-dangle
+		for ( i = 0; i < this._length; i++ ) {
+			v = fcn.call( thisArg, buf[ GETTER ]( i * BYTES_PER_ELEMENT, this._isLE ), i, this );
+			obuf[ SETTER ]( i * BYTES_PER_ELEMENT, v, this._isLE );
+		}
+		return out;
+	});
+
 	/**
 	* Sets an array element.
 	*