Auto-generated commit

README.md

@@ -45,12 +45,14 @@ npm install @stdlib/ndarray
 
 Alternatively,
 
--   To load the package in a website via a `script` tag without installation and bundlers, use the [ES Module][es-module] available on the [`esm` branch][esm-url].
--   If you are using Deno, visit the [`deno` branch][deno-url].
--   For use in Observable, or in browser/node environments, use the [Universal Module Definition (UMD)][umd] build available on the [`umd` branch][umd-url].
+-   To load the package in a website via a `script` tag without installation and bundlers, use the [ES Module][es-module] available on the [`esm`][esm-url] branch (see [README][esm-readme]).
+-   If you are using Deno, visit the [`deno`][deno-url] branch (see [README][deno-readme] for usage intructions).
+-   For use in Observable, or in browser/node environments, use the [Universal Module Definition (UMD)][umd] build available on the [`umd`][umd-url] branch (see [README][umd-readme]).
 
 The [branches.md][branches-url] file summarizes the available branches and displays a diagram illustrating their relationships.
 
+To view installation and usage instructions specific to each branch build, be sure to explicitly navigate to the respective README files on each branch, as linked to above.
+
 </section>
 
 <section class="usage">
@@ -246,8 +248,11 @@ Copyright &copy; 2016-2024. The Stdlib [Authors][stdlib-authors].
 [es-module]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Modules
 
 [deno-url]: https://github.com/stdlib-js/ndarray/tree/deno
+[deno-readme]: https://github.com/stdlib-js/ndarray/blob/deno/README.md
 [umd-url]: https://github.com/stdlib-js/ndarray/tree/umd
+[umd-readme]: https://github.com/stdlib-js/ndarray/blob/umd/README.md
 [esm-url]: https://github.com/stdlib-js/ndarray/tree/esm
+[esm-readme]: https://github.com/stdlib-js/ndarray/blob/esm/README.md
 [branches-url]: https://github.com/stdlib-js/ndarray/blob/main/branches.md
 
 [stdlib-license]: https://raw.githubusercontent.com/stdlib-js/ndarray/main/LICENSE

at/README.md

@@ -0,0 +1,179 @@
+<!--
+
+@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.
+
+-->
+
+# at
+
+> Return an [`ndarray`][@stdlib/ndarray/ctor] element.
+
+<!-- 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 at = require( '@stdlib/ndarray/at' );
+```
+
+#### at( x\[, ...indices] )
+
+Returns an [`ndarray`][@stdlib/ndarray/ctor] element.
+
+```javascript
+var array = require( '@stdlib/ndarray/array' );
+
+var x = array( [ [ 1, 2 ], [ 3, 4 ] ] );
+// returns <ndarray>
+
+var v = at( x, 0, 0 );
+// returns 1
+
+v = at( x, 0, 1 );
+// returns 2
+
+v = at( x, 1, 0 );
+// returns 3
+
+v = at( x, 1, 1 );
+// returns 4
+```
+
+The function accepts the following arguments:
+
+-   **x**: input [`ndarray`][@stdlib/ndarray/ctor].
+-   **indices**: index arguments. The number of index arguments **must** equal the number of dimensions.
+
+</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">
+
+## Notes
+
+-   If provided out-of-bounds indices, the function always returns `undefined`.
+
+    ```javascript
+    var array = require( '@stdlib/ndarray/array' );
+
+    var x = array( [ [ 1, 2 ], [ 3, 4 ] ] );
+    // returns <ndarray>
+
+    var v = at( x, 10, 20 );
+    // returns undefined
+    ```
+
+-   Negative indices are resolved relative to the last element along the respective dimension, with the last element corresponding to `-1`.
+
+    ```javascript
+    var array = require( '@stdlib/ndarray/array' );
+
+    var x = array( [ [ 1, 2 ], [ 3, 4 ] ] );
+    // returns <ndarray>
+
+    var v = at( x, -1, -1 );
+    // returns 4
+
+    v = at( x, -2, -2 );
+    // returns 1
+    ```
+
+</section>
+
+<!-- /.notes -->
+
+<!-- Package usage examples. -->
+
+<section class="examples">
+
+## Examples
+
+<!-- eslint no-undef: "error" -->
+
+<!-- eslint-disable new-cap -->
+
+```javascript
+var cartesianProduct = require( '@stdlib/array/cartesian-product' );
+var zeroTo = require( '@stdlib/array/zero-to' );
+var discreteUniform = require( '@stdlib/random/array/discrete-uniform' );
+var array = require( '@stdlib/ndarray/array' );
+var at = require( '@stdlib/ndarray/at' );
+
+// Define a two-dimensional array:
+var shape = [ 5, 5 ];
+var x = array( discreteUniform( 25, -100, 100 ), {
+    'shape': shape
+});
+
+// Define lists of dimension indices:
+var i0 = zeroTo( shape[ 0 ], 'generic' );
+var i1 = zeroTo( shape[ 1 ], 'generic' );
+
+// Create a list of index pairs:
+var indices = cartesianProduct( i0, i1 );
+
+// Print array contents...
+var idx;
+var i;
+for ( i = 0; i < x.length; i++ ) {
+    idx = indices[ i ];
+    console.log( 'x[%d,%d] = %d', idx[ 0 ], idx[ 1 ], at( x, idx[ 0 ], idx[ 1 ] ) );
+}
+```
+
+</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">
+
+[@stdlib/ndarray/ctor]: https://github.com/stdlib-js/ndarray/tree/main/ctor
+
+</section>
+
+<!-- /.links -->

at/benchmark/benchmark.js

@@ -0,0 +1,56 @@
+/**
+* @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 uniform = require( '@stdlib/random/base/uniform' ).factory;
+var filled2dBy = require( '@stdlib/array/base/filled2d-by' );
+var isnan = require( '@stdlib/math/base/assert/is-nan' );
+var array = require( './../../array' );
+var pkg = require( './../package.json' ).name;
+var at = require( './../lib' );
+
+
+// MAIN //
+
+bench( pkg, function benchmark( b ) {
+	var x;
+	var v;
+	var i;
+	var j;
+
+	x = array( filled2dBy( [ 10, 10 ], uniform( 0.0, 10.0 ) ) );
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		j = ( i%20 ) - 10;
+		v = at( x, j, j );
+		if ( v !== v ) {
+			b.fail( 'should not return NaN' );
+		}
+	}
+	b.toc();
+	if ( isnan( v ) ) {
+		b.fail( 'should not return NaN' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});

at/docs/repl.txt

@@ -0,0 +1,34 @@
+
+{{alias}}( x[, ...indices] )
+    Returns an ndarray element.
+
+    Negative indices are resolved relative to the last element along the
+    respective dimension, with the last element corresponding to `-1`.
+
+    If provided out-of-bounds indices, the function always returns `undefined`.
+
+    Parameters
+    ----------
+    x: ndarray
+        Input ndarray.
+
+    indices: ...integer (optional)
+        Index arguments. The number of index arguments must equal the number of
+        dimensions.
+
+    Returns
+    -------
+    out: any
+        Element value.
+
+    Examples
+    --------
+    > var x = {{alias:@stdlib/ndarray/array}}( [ [ 1, 2 ], [ 3, 4 ] ] );
+    > {{alias}}( x, 0, 1 )
+    2
+    > {{alias}}( x, 1, 0 )
+    3
+
+    See Also
+    --------
+