feat: add filter method to array/complex128

PR-URL: 	#1225
Reviewed-by: Athan Reines <kgryte@gmail.com>

Author: Jaysukh-409

lib/node_modules/@stdlib/array/complex128/README.md

@@ -856,6 +856,81 @@ var count = context.count;
 // returns 3
 ```
 
+<a name="method-filter"></a>
+
+#### Complex128Array.prototype.filter( predicate\[, thisArg] )
+
+Returns a new array containing the elements of an array which pass a test implemented by a predicate function.
+
+```javascript
+var real = require( '@stdlib/complex/real' );
+var imag = require( '@stdlib/complex/imag' );
+
+function predicate( v ) {
+    return ( real( v ) === imag( v ) );
+}
+
+var arr = new Complex128Array( 3 );
+
+// Set the first three elements:
+arr.set( [ 1.0, -1.0 ], 0 );
+arr.set( [ 2.0, 2.0 ], 1 );
+arr.set( [ 3.0, -3.0 ], 2 );
+
+var out = arr.filter( predicate );
+// returns <Complex128Array>
+
+var len = out.length;
+// returns 1
+
+var z = out.get( 0 );
+// returns <Complex128>
+
+var re = real( z );
+// returns 2.0
+
+var im = imag( z );
+// returns 2.0
+```
+
+The `predicate` 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
+var real = require( '@stdlib/complex/real' );
+var imag = require( '@stdlib/complex/imag' );
+
+function predicate( v, i ) {
+    this.count += 1;
+    return ( i >= 0 && real( v ) === imag( v ) );
+}
+
+var arr = new Complex128Array( 3 );
+
+var context = {
+    'count': 0
+};
+
+// Set the first three elements:
+arr.set( [ 1.0, -1.0 ], 0 );
+arr.set( [ 2.0, 2.0 ], 1 );
+arr.set( [ 3.0, 3.0 ], 2 );
+
+var out = arr.filter( predicate, context );
+// returns <Complex128Array>
+
+var len = out.length;
+// returns 2
+
+var count = context.count;
+// returns 3
+```
+
 <a name="method-find"></a>
 
 #### Complex128Array.prototype.find( predicate\[, thisArg] )

lib/node_modules/@stdlib/array/complex128/benchmark/benchmark.filter.js

@@ -0,0 +1,56 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2023 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 isComplex128 = require( '@stdlib/assert/is-complex128' );
+var isComplex128Array = require( '@stdlib/assert/is-complex128array' );
+var pkg = require( './../package.json' ).name;
+var Complex128Array = require( './../lib' );
+
+
+// MAIN //
+
+bench( pkg+':filter', function benchmark( b ) {
+	var out;
+	var arr;
+	var i;
+
+	arr = new Complex128Array( [ 1, 2, 3, 4, 5, 6 ] );
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		out = arr.filter( predicate );
+		if ( typeof out !== 'object' ) {
+			b.fail( 'should return an object' );
+		}
+	}
+	b.toc();
+	if ( !isComplex128Array( out ) ) {
+		b.fail( 'should return a Complex128Array' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+
+	function predicate( v ) {
+		return isComplex128( v );
+	}
+});

lib/node_modules/@stdlib/array/complex128/benchmark/benchmark.filter.length.js

@@ -0,0 +1,118 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2023 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 isComplex128Array = require( '@stdlib/assert/is-complex128array' );
+var pow = require( '@stdlib/math/base/special/pow' );
+var Complex128 = require( '@stdlib/complex/float64' );
+var real = require( '@stdlib/complex/real' );
+var imag = require( '@stdlib/complex/imag' );
+var pkg = require( './../package.json' ).name;
+var Complex128Array = require( './../lib' );
+
+
+// FUNCTIONS //
+
+/**
+* Predicate function.
+*
+* @private
+* @param {Complex128} value - array element
+* @param {NonNegativeInteger} idx - array element index
+* @param {Complex128Array} arr - array instance
+* @returns {boolean} boolean indicating whether a value passes a test
+*/
+function predicate( value ) {
+	return ( real( value ) === imag( value ) );
+}
+
+/**
+* Creates a benchmark function.
+*
+* @private
+* @param {PositiveInteger} len - array length
+* @returns {Function} benchmark function
+*/
+function createBenchmark( len ) {
+	var arr;
+	var i;
+
+	arr = [];
+	for ( i = 0; i < len; i++ ) {
+		arr.push( new Complex128( i, i ) );
+	}
+	arr = new Complex128Array( arr );
+
+	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.filter( predicate );
+			if ( typeof out !== 'object' ) {
+				b.fail( 'should return an object' );
+			}
+		}
+		b.toc();
+		if ( !isComplex128Array( out ) ) {
+			b.fail( 'should return a Complex128Array' );
+		}
+		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+':filter:len='+len, f );
+	}
+}
+
+main();

lib/node_modules/@stdlib/array/complex128/docs/types/index.d.ts

@@ -343,6 +343,44 @@ declare class Complex128Array implements Complex128ArrayInterface {
 	*/
 	every<U = unknown>( predicate: Predicate<U>, thisArg?: ThisParameterType<Predicate<U>> ): boolean;
 
+	/**
+	* Returns a new array containing the elements of an array which pass a test implemented by a predicate function.
+	*
+	* @param predicate - test function
+	* @param thisArg - execution context
+	* @returns new array containing elements which pass a test implemented by a predicate function
+	*
+	* @example
+	* var real = require( '@stdlib/complex/real' );
+	* var imag = require( '@stdlib/complex/imag' );
+	*
+	* function predicate( v ) {
+	*     return ( real( v ) === imag( v ) );
+	* }
+	*
+	* var arr = new Complex128Array( 3 );
+	*
+	* arr.set( [ 1.0, -1.0 ], 0 );
+	* arr.set( [ 2.0, 2.0 ], 1 );
+	* arr.set( [ 3.0, -3.0 ], 2 );
+	*
+	* var out = arr.filter( predicate );
+	* // returns <Complex128Array>
+	*
+	* var len = out.length;
+	* // returns 1
+	*
+	* var z = out.get( 0 );
+	* // returns <Complex128>
+	*
+	* var re = real( z );
+	* // returns 2.0
+	*
+	* var im = imag( z );
+	* // returns 2.0
+	*/
+	filter<U = unknown>( predicate: Predicate<U>, thisArg?: ThisParameterType<Predicate<U>> ): Complex128Array;
+
 	/**
 	* Returns the first element in an array for which a predicate function returns a truthy value.
 	*

lib/node_modules/@stdlib/array/complex128/lib/main.js

@@ -920,6 +920,69 @@ setReadOnly( Complex128Array.prototype, 'every', function every( predicate, this
 	return true;
 });
 
+/**
+* Returns a new array containing the elements of an array which pass a test implemented by a predicate function.
+*
+* @name filter
+* @memberof Complex128Array.prototype
+* @type {Function}
+* @param {Function} predicate - test function
+* @param {*} [thisArg] - predicate function execution context
+* @throws {TypeError} `this` must be a complex number array
+* @throws {TypeError} first argument must be a function
+* @returns {Complex128Array} complex number array
+*
+* @example
+* var real = require( '@stdlib/complex/real' );
+* var imag = require( '@stdlib/complex/imag' );
+*
+* function predicate( v ) {
+*     return ( real( v ) === imag( v ) );
+* }
+*
+* var arr = new Complex128Array( 3 );
+*
+* arr.set( [ 1.0, -1.0 ], 0 );
+* arr.set( [ 2.0, 2.0 ], 1 );
+* arr.set( [ 3.0, -3.0 ], 2 );
+*
+* var out = arr.filter( predicate );
+* // returns <Complex128Array>
+*
+* var len = out.length;
+* // returns 1
+*
+* var z = out.get( 0 );
+* // returns <Complex128>
+*
+* var re = real( z );
+* // returns 2.0
+*
+* var im = imag( z );
+* // returns 2.0
+*/
+setReadOnly( Complex128Array.prototype, 'filter', function filter( predicate, thisArg ) {
+	var buf;
+	var out;
+	var i;
+	var z;
+	if ( !isComplexArray( this ) ) {
+		throw new TypeError( 'invalid invocation. `this` is not a complex number array.' );
+	}
+	if ( !isFunction( predicate ) ) {
+		throw new TypeError( format( 'invalid argument. First argument must be a function. Value: `%s`.', predicate ) );
+	}
+	buf = this._buffer;
+	out = [];
+	for ( i = 0; i < this._length; i++ ) {
+		z = getComplex128( buf, i );
+		if ( predicate.call( thisArg, z, i, this ) ) {
+			out.push( z );
+		}
+	}
+	return new this.constructor( out );
+});
+
 /**
 * Returns the first element in an array for which a predicate function returns a truthy value.
 *