feat: add array/base/last

lib/node_modules/@stdlib/array/base/last/README.md

@@ -0,0 +1,123 @@
+<!--
+
+@license Apache-2.0
+
+Copyright (c) 2022 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.
+
+-->
+
+# last
+
+> Return the last element of an array-like object.
+
+<!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->
+
+<section class="intro">
+
+</section>
+
+<!-- /.intro -->
+
+<!-- Package usage documentation. -->
+
+<section class="usage">
+
+## Usage
+
+```javascript
+var last = require( '@stdlib/array/base/last' );
+```
+
+#### last( x )
+
+Returns the last element of an array-like object.
+
+```javascript
+var x = [ 1, 2, 3 ];
+
+var out = last( x );
+// returns 3
+```
+
+</section>
+
+<!-- /.usage -->
+
+<!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
+
+<section class="notes">
+
+</section>
+
+<!-- /.notes -->
+
+<!-- Package usage examples. -->
+
+<section class="examples">
+
+## Examples
+
+<!-- eslint no-undef: "error" -->
+
+```javascript
+var Complex64Array = require( '@stdlib/array/complex64' );
+var realf = require( '@stdlib/complex/realf' );
+var imagf = require( '@stdlib/complex/imagf' );
+var last = require( '@stdlib/array/base/last' );
+
+// Create a complex number array:
+var arr = new Complex64Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ] );
+
+// Return the last element:
+var out = last( arr );
+// returns <Complex64>
+
+var re = realf( out );
+// returns 5.0
+
+var im = imagf( out );
+// returns 6.0
+
+console.log( '%d + %di', re, im );
+// => '5 + 6i'
+```
+
+</section>
+
+<!-- /.examples -->
+
+<!-- Section to include cited references. If references are included, add a horizontal rule *before* the section. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
+
+<section class="references">
+
+</section>
+
+<!-- /.references -->
+
+<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->
+
+<section class="related">
+
+</section>
+
+<!-- /.related -->
+
+<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
+
+<section class="links">
+
+</section>
+
+<!-- /.links -->

lib/node_modules/@stdlib/array/base/last/benchmark/benchmark.js

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+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2022 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 discreteUniform = require( '@stdlib/random/base/discrete-uniform' ).factory;
+var Complex64Array = require( '@stdlib/array/complex64' );
+var pow = require( '@stdlib/math/base/special/pow' );
+var filledBy = require( '@stdlib/array/filled-by' );
+var isnanf = require( '@stdlib/math/base/assert/is-nanf' );
+var pkg = require( './../package.json' ).name;
+var last = require( './../lib' );
+
+
+// VARIABLES //
+
+var rand = discreteUniform( 0, 127 );
+
+
+// FUNCTIONS //
+
+/**
+* Creates a benchmark function.
+*
+* @private
+* @param {PositiveInteger} len - array length
+* @returns {Function} benchmark function
+*/
+function createBenchmark( len ) {
+	var buf = filledBy( len*2, 'float32', rand );
+	var arr = new Complex64Array( buf.buffer );
+	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 = last( arr );
+			if ( isnanf( out ) ) {
+				b.fail( 'should not return NaN' );
+			}
+		}
+		b.toc();
+		if ( isnanf( out ) ) {
+			b.fail( 'should not return NaN' );
+		}
+		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+':len='+len, f );
+	}
+}
+
+main();

lib/node_modules/@stdlib/array/base/last/docs/repl.txt

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+
+{{alias}}( arr )
+    Returns the last element of an array-like object.
+
+    Parameters
+    ----------
+    arr: ArrayLikeObject
+        Input array.
+
+    Returns
+    -------
+    out: any
+        Last element.
+
+    Examples
+    --------
+    > var out = {{alias}}( [ 1, 2, 3 ] )
+    3
+
+    See Also
+    --------
+

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

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+/*
+* @license Apache-2.0
+*
+* Copyright (c) 2022 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.
+*/
+
+// TypeScript Version: 2.0
+
+/// <reference types="@stdlib/types"/>
+
+import { Collection } from '@stdlib/types/object';
+
+/**
+* Returns the last element of an array-like object.
+*
+* @param arr - input array
+* @returns last element
+*
+* @example
+* var arr = [ 1, 2, 3 ];
+*
+* var out = last( x );
+* // returns 3
+*/
+declare function last( arr: Collection ): any;
+
+
+// EXPORTS //
+
+export = last;

lib/node_modules/@stdlib/array/base/last/docs/types/test.ts

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+/*
+* @license Apache-2.0
+*
+* Copyright (c) 2022 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.
+*/
+
+import last = require( './index' );
+
+
+// TESTS //
+
+// The function returns the last element in array...
+{
+	last( [ 1, 2, 3 ] ); // $ExpectType any
+}
+
+// The compiler throws an error if the function is provided an argument which is not a collection...
+{
+	last( 5 ); // $ExpectError
+	last( true ); // $ExpectError
+	last( false ); // $ExpectError
+	last( null ); // $ExpectError
+	last( {} ); // $ExpectError
+}
+
+// The compiler throws an error if the function is provided an unsupported number of arguments...
+{
+	last(); // $ExpectError
+	last( [ 1, 2, 3 ], 2 ); // $ExpectError
+}

lib/node_modules/@stdlib/array/base/last/examples/index.js

@@ -0,0 +1,40 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2022 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';
+
+var Complex64Array = require( '@stdlib/array/complex64' );
+var realf = require( '@stdlib/complex/realf' );
+var imagf = require( '@stdlib/complex/imagf' );
+var last = require( './../lib' );
+
+// Create a complex number array:
+var arr = new Complex64Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ] );
+
+// Return the last element:
+var out = last( arr );
+// returns <Complex64>
+
+var re = realf( out );
+// returns 5.0
+
+var im = imagf( out );
+// returns 6.0
+
+console.log( '%d + %di', re, im );
+// => '5 + 6i'