From 983eafd3bbfca27598f72beb7bfdfc5944765ee7 Mon Sep 17 00:00:00 2001
From: headlessNode <harriskhan047@outlook.com>
Date: Sat, 25 Apr 2026 18:30:13 +0500
Subject: [PATCH] feat: add ndarray/base/to-rotl90

---
type: pre_commit_static_analysis_report
description: Results of running static analysis checks when committing changes.
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---
---
 .../@stdlib/ndarray/base/to-rotl90/README.md  | 152 +++++
 .../base/to-rotl90/benchmark/benchmark.js     | 272 +++++++++
 .../ndarray/base/to-rotl90/docs/repl.txt      |  38 ++
 .../base/to-rotl90/docs/types/index.d.ts      |  46 ++
 .../ndarray/base/to-rotl90/docs/types/test.ts |  76 +++
 .../ndarray/base/to-rotl90/examples/index.js  |  51 ++
 .../ndarray/base/to-rotl90/lib/index.js       |  44 ++
 .../ndarray/base/to-rotl90/lib/main.js        |  65 +++
 .../ndarray/base/to-rotl90/package.json       |  66 +++
 .../ndarray/base/to-rotl90/test/test.js       | 538 ++++++++++++++++++
 10 files changed, 1348 insertions(+)
 create mode 100644 lib/node_modules/@stdlib/ndarray/base/to-rotl90/README.md
 create mode 100644 lib/node_modules/@stdlib/ndarray/base/to-rotl90/benchmark/benchmark.js
 create mode 100644 lib/node_modules/@stdlib/ndarray/base/to-rotl90/docs/repl.txt
 create mode 100644 lib/node_modules/@stdlib/ndarray/base/to-rotl90/docs/types/index.d.ts
 create mode 100644 lib/node_modules/@stdlib/ndarray/base/to-rotl90/docs/types/test.ts
 create mode 100644 lib/node_modules/@stdlib/ndarray/base/to-rotl90/examples/index.js
 create mode 100644 lib/node_modules/@stdlib/ndarray/base/to-rotl90/lib/index.js
 create mode 100644 lib/node_modules/@stdlib/ndarray/base/to-rotl90/lib/main.js
 create mode 100644 lib/node_modules/@stdlib/ndarray/base/to-rotl90/package.json
 create mode 100644 lib/node_modules/@stdlib/ndarray/base/to-rotl90/test/test.js

diff --git a/lib/node_modules/@stdlib/ndarray/base/to-rotl90/README.md b/lib/node_modules/@stdlib/ndarray/base/to-rotl90/README.md
new file mode 100644
index 000000000000..c5236cf3ef5f
--- /dev/null
+++ b/lib/node_modules/@stdlib/ndarray/base/to-rotl90/README.md
@@ -0,0 +1,152 @@
+<!--
+
+@license Apache-2.0
+
+Copyright (c) 2026 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.
+
+-->
+
+# toRotl90
+
+> Return a new ndarray where a matrix (or a stack of matrices) is rotated 90 degrees counterclockwise.
+
+<!-- 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 toRotl90 = require( '@stdlib/ndarray/base/to-rotl90' );
+```
+
+#### toRotl90( x, k )
+
+Returns a new ndarray where a matrix (or a stack of matrices) is rotated 90 degrees counterclockwise.
+
+```javascript
+var array = require( '@stdlib/ndarray/array' );
+
+var x = array( [ [ 1, 2 ], [ 3, 4 ] ] );
+// returns <ndarray>[ [ 1, 2 ], [ 3, 4 ] ]
+
+var y = toRotl90( x, 1 );
+// returns <ndarray>[ [ 2, 4 ], [ 1, 3 ] ]
+```
+
+The function accepts the following arguments:
+
+-   **x**: input ndarray.
+-   **k**: number of times to rotate by 90 degrees. Positive values rotate counterclockwise. Negative values rotate clockwise.
+
+</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 `k > 0`, the function rotates the matrix counterclockwise.
+-   If `k < 0`, the function rotates the matrix clockwise.
+-   If provided an ndarray with fewer than two dimensions, the function does not perform a rotation and simply returns a copy of the input ndarray.
+
+</section>
+
+<!-- /.notes -->
+
+<!-- Package usage examples. -->
+
+<section class="examples">
+
+## Examples
+
+<!-- eslint no-undef: "error" -->
+
+```javascript
+var array = require( '@stdlib/ndarray/array' );
+var ndarray2array = require( '@stdlib/ndarray/to-array' );
+var toRotl90 = require( '@stdlib/ndarray/base/to-rotl90' );
+
+// Create a 2x3 matrix:
+var x = array( [ [ 1, 2, 3 ], [ 4, 5, 6 ] ] );
+
+// Rotate 90 degrees counterclockwise:
+var y = toRotl90( x, 1 );
+var arr = ndarray2array( y );
+// returns [ [ 3, 6 ], [ 2, 5 ], [ 1, 4 ] ]
+
+// Rotate 180 degrees:
+y = toRotl90( x, 2 );
+arr = ndarray2array( y );
+// returns [ [ 6, 5, 4 ], [ 3, 2, 1 ] ]
+
+// Rotate 270 degrees counterclockwise (equivalent to 90 degrees clockwise):
+y = toRotl90( x, 3 );
+arr = ndarray2array( y );
+// returns [ [ 4, 1 ], [ 5, 2 ], [ 6, 3 ] ]
+
+// Rotate 360 degrees (equivalent to no rotation):
+y = toRotl90( x, 4 );
+arr = ndarray2array( y );
+// returns [ [ 1, 2, 3 ], [ 4, 5, 6 ] ]
+
+// Rotate 90 degrees clockwise (equivalent to k=3):
+y = toRotl90( x, -1 );
+arr = ndarray2array( y );
+// returns [ [ 4, 1 ], [ 5, 2 ], [ 6, 3 ] ]
+```
+
+</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">
+
+<!-- <related-links> -->
+
+<!-- </related-links> -->
+
+</section>
+
+<!-- /.links -->
diff --git a/lib/node_modules/@stdlib/ndarray/base/to-rotl90/benchmark/benchmark.js b/lib/node_modules/@stdlib/ndarray/base/to-rotl90/benchmark/benchmark.js
new file mode 100644
index 000000000000..b71a1a7b1b72
--- /dev/null
+++ b/lib/node_modules/@stdlib/ndarray/base/to-rotl90/benchmark/benchmark.js
@@ -0,0 +1,272 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 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 isndarrayLike = require( '@stdlib/assert/is-ndarray-like' );
+var baseEmpty = require( '@stdlib/ndarray/base/empty' );
+var empty = require( '@stdlib/ndarray/empty' );
+var format = require( '@stdlib/string/format' );
+var pkg = require( './../package.json' ).name;
+var toRotl90 = require( './../lib' );
+
+
+// MAIN //
+
+bench( format( '%s::2d,base', pkg ), function benchmark( b ) {
+	var values;
+	var out;
+	var i;
+
+	values = [
+		baseEmpty( 'float64', [ 2, 2 ], 'row-major' ),
+		baseEmpty( 'float32', [ 2, 2 ], 'row-major' ),
+		baseEmpty( 'int32', [ 2, 2 ], 'row-major' ),
+		baseEmpty( 'complex128', [ 2, 2 ], 'row-major' ),
+		baseEmpty( 'generic', [ 2, 2 ], 'row-major' )
+	];
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		out = toRotl90( values[ i%values.length ], 1 );
+		if ( typeof out !== 'object' ) {
+			b.fail( 'should return an ndarray' );
+		}
+	}
+	b.toc();
+	if ( !isndarrayLike( out ) ) {
+		b.fail( 'should return an ndarray' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});
+
+bench( format( '%s::2d,non-base', pkg ), function benchmark( b ) {
+	var values;
+	var out;
+	var i;
+
+	/* eslint-disable object-curly-newline, stdlib/line-closing-bracket-spacing */
+
+	values = [
+		empty( [ 2, 2 ], { 'dtype': 'float64' } ),
+		empty( [ 2, 2 ], { 'dtype': 'float32' } ),
+		empty( [ 2, 2 ], { 'dtype': 'int32' } ),
+		empty( [ 2, 2 ], { 'dtype': 'complex128' } ),
+		empty( [ 2, 2 ], { 'dtype': 'generic' } )
+	];
+
+	/* eslint-enable object-curly-newline, stdlib/line-closing-bracket-spacing */
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		out = toRotl90( values[ i%values.length ], 1 );
+		if ( typeof out !== 'object' ) {
+			b.fail( 'should return an ndarray' );
+		}
+	}
+	b.toc();
+	if ( !isndarrayLike( out ) ) {
+		b.fail( 'should return an ndarray' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});
+
+bench( format( '%s::3d,base', pkg ), function benchmark( b ) {
+	var values;
+	var out;
+	var i;
+
+	values = [
+		baseEmpty( 'float64', [ 2, 2, 2 ], 'row-major' ),
+		baseEmpty( 'float32', [ 2, 2, 2 ], 'row-major' ),
+		baseEmpty( 'int32', [ 2, 2, 2 ], 'row-major' ),
+		baseEmpty( 'complex128', [ 2, 2, 2 ], 'row-major' ),
+		baseEmpty( 'generic', [ 2, 2, 2 ], 'row-major' )
+	];
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		out = toRotl90( values[ i%values.length ], 1 );
+		if ( typeof out !== 'object' ) {
+			b.fail( 'should return an ndarray' );
+		}
+	}
+	b.toc();
+	if ( !isndarrayLike( out ) ) {
+		b.fail( 'should return an ndarray' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});
+
+bench( format( '%s::3d,non-base', pkg ), function benchmark( b ) {
+	var values;
+	var out;
+	var i;
+
+	/* eslint-disable object-curly-newline, stdlib/line-closing-bracket-spacing */
+
+	values = [
+		empty( [ 2, 2, 2 ], { 'dtype': 'float64' } ),
+		empty( [ 2, 2, 2 ], { 'dtype': 'float32' } ),
+		empty( [ 2, 2, 2 ], { 'dtype': 'int32' } ),
+		empty( [ 2, 2, 2 ], { 'dtype': 'complex128' } ),
+		empty( [ 2, 2, 2 ], { 'dtype': 'generic' } )
+	];
+
+	/* eslint-enable object-curly-newline, stdlib/line-closing-bracket-spacing */
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		out = toRotl90( values[ i%values.length ], 1 );
+		if ( typeof out !== 'object' ) {
+			b.fail( 'should return an ndarray' );
+		}
+	}
+	b.toc();
+	if ( !isndarrayLike( out ) ) {
+		b.fail( 'should return an ndarray' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});
+
+bench( format( '%s::4d,base', pkg ), function benchmark( b ) {
+	var values;
+	var out;
+	var i;
+
+	values = [
+		baseEmpty( 'float64', [ 2, 2, 2, 2 ], 'row-major' ),
+		baseEmpty( 'float32', [ 2, 2, 2, 2 ], 'row-major' ),
+		baseEmpty( 'int32', [ 2, 2, 2, 2 ], 'row-major' ),
+		baseEmpty( 'complex128', [ 2, 2, 2, 2 ], 'row-major' ),
+		baseEmpty( 'generic', [ 2, 2, 2, 2 ], 'row-major' )
+	];
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		out = toRotl90( values[ i%values.length ], 1 );
+		if ( typeof out !== 'object' ) {
+			b.fail( 'should return an ndarray' );
+		}
+	}
+	b.toc();
+	if ( !isndarrayLike( out ) ) {
+		b.fail( 'should return an ndarray' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});
+
+bench( format( '%s::4d,non-base', pkg ), function benchmark( b ) {
+	var values;
+	var out;
+	var i;
+
+	/* eslint-disable object-curly-newline, stdlib/line-closing-bracket-spacing */
+
+	values = [
+		empty( [ 2, 2, 2, 2 ], { 'dtype': 'float64' } ),
+		empty( [ 2, 2, 2, 2 ], { 'dtype': 'float32' } ),
+		empty( [ 2, 2, 2, 2 ], { 'dtype': 'int32' } ),
+		empty( [ 2, 2, 2, 2 ], { 'dtype': 'complex128' } ),
+		empty( [ 2, 2, 2, 2 ], { 'dtype': 'generic' } )
+	];
+
+	/* eslint-enable object-curly-newline, stdlib/line-closing-bracket-spacing */
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		out = toRotl90( values[ i%values.length ], 1 );
+		if ( typeof out !== 'object' ) {
+			b.fail( 'should return an ndarray' );
+		}
+	}
+	b.toc();
+	if ( !isndarrayLike( out ) ) {
+		b.fail( 'should return an ndarray' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});
+
+bench( format( '%s::5d,base', pkg ), function benchmark( b ) {
+	var values;
+	var out;
+	var i;
+
+	values = [
+		baseEmpty( 'float64', [ 2, 2, 2, 2, 2 ], 'row-major' ),
+		baseEmpty( 'float32', [ 2, 2, 2, 2, 2 ], 'row-major' ),
+		baseEmpty( 'int32', [ 2, 2, 2, 2, 2 ], 'row-major' ),
+		baseEmpty( 'complex128', [ 2, 2, 2, 2, 2 ], 'row-major' ),
+		baseEmpty( 'generic', [ 2, 2, 2, 2, 2 ], 'row-major' )
+	];
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		out = toRotl90( values[ i%values.length ], 1 );
+		if ( typeof out !== 'object' ) {
+			b.fail( 'should return an ndarray' );
+		}
+	}
+	b.toc();
+	if ( !isndarrayLike( out ) ) {
+		b.fail( 'should return an ndarray' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});
+
+bench( format( '%s::5d,non-base', pkg ), function benchmark( b ) {
+	var values;
+	var out;
+	var i;
+
+	/* eslint-disable object-curly-newline, stdlib/line-closing-bracket-spacing */
+
+	values = [
+		empty( [ 2, 2, 2, 2, 2 ], { 'dtype': 'float64' } ),
+		empty( [ 2, 2, 2, 2, 2 ], { 'dtype': 'float32' } ),
+		empty( [ 2, 2, 2, 2, 2 ], { 'dtype': 'int32' } ),
+		empty( [ 2, 2, 2, 2, 2 ], { 'dtype': 'complex128' } ),
+		empty( [ 2, 2, 2, 2, 2 ], { 'dtype': 'generic' } )
+	];
+
+	/* eslint-enable object-curly-newline, stdlib/line-closing-bracket-spacing */
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		out = toRotl90( values[ i%values.length ], 1 );
+		if ( typeof out !== 'object' ) {
+			b.fail( 'should return an ndarray' );
+		}
+	}
+	b.toc();
+	if ( !isndarrayLike( out ) ) {
+		b.fail( 'should return an ndarray' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});
diff --git a/lib/node_modules/@stdlib/ndarray/base/to-rotl90/docs/repl.txt b/lib/node_modules/@stdlib/ndarray/base/to-rotl90/docs/repl.txt
new file mode 100644
index 000000000000..d9eadc3c933b
--- /dev/null
+++ b/lib/node_modules/@stdlib/ndarray/base/to-rotl90/docs/repl.txt
@@ -0,0 +1,38 @@
+
+{{alias}}( x, k )
+    Returns a new ndarray where a matrix (or a stack of matrices) is rotated 90
+    degrees counterclockwise.
+
+    If `k > 0`, the function rotates the matrix counterclockwise. If `k < 0`,
+    the function rotates the matrix clockwise.
+
+    If provided an ndarray with fewer than two dimensions, the function does not
+    perform a rotation and simply returns a copy of the input ndarray.
+
+    Parameters
+    ----------
+    x: ndarray
+        Input array.
+
+    k: integer
+        Number of times to rotate by 90 degrees.
+
+    Returns
+    -------
+    out: ndarray
+        Output array.
+
+    Examples
+    --------
+    > var x = {{alias:@stdlib/ndarray/array}}( [ [ 1, 2 ], [ 3, 4 ] ] )
+    <ndarray>[ [ 1, 2 ], [ 3, 4 ] ]
+    > var y = {{alias}}( x, 1 )
+    <ndarray>[ [ 2, 4 ], [ 1, 3 ] ]
+    > y = {{alias}}( x, 2 )
+    <ndarray>[ [ 4, 3 ], [ 2, 1 ] ]
+    > y = {{alias}}( x, 3 )
+    <ndarray>[ [ 3, 1 ], [ 4, 2 ] ]
+
+    See Also
+    --------
+
diff --git a/lib/node_modules/@stdlib/ndarray/base/to-rotl90/docs/types/index.d.ts b/lib/node_modules/@stdlib/ndarray/base/to-rotl90/docs/types/index.d.ts
new file mode 100644
index 000000000000..b41653631731
--- /dev/null
+++ b/lib/node_modules/@stdlib/ndarray/base/to-rotl90/docs/types/index.d.ts
@@ -0,0 +1,46 @@
+/*
+* @license Apache-2.0
+*
+* Copyright (c) 2026 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: 4.1
+
+/// <reference types="@stdlib/types"/>
+
+import { typedndarray } from '@stdlib/types/ndarray';
+
+/**
+* Returns a new ndarray where a matrix (or a stack of matrices) is rotated 90 degrees counterclockwise.
+*
+* @param x - input array
+* @param k - number of times to rotate by 90 degrees
+* @returns output array
+*
+* @example
+* var array = require( '@stdlib/ndarray/array' );
+*
+* var x = array( [ [ 1, 2 ], [ 3, 4 ] ] );
+* // returns <ndarray>[ [ 1, 2 ], [ 3, 4 ] ]
+*
+* var y = toRotl90( x, 1 );
+* // returns <ndarray>[ [ 2, 4 ], [ 1, 3 ] ]
+*/
+declare function toRotl90<T = unknown, U extends typedndarray<T> = typedndarray<T>>( x: U, k: number ): U;
+
+
+// EXPORTS //
+
+export = toRotl90;
diff --git a/lib/node_modules/@stdlib/ndarray/base/to-rotl90/docs/types/test.ts b/lib/node_modules/@stdlib/ndarray/base/to-rotl90/docs/types/test.ts
new file mode 100644
index 000000000000..ba518b9e5c42
--- /dev/null
+++ b/lib/node_modules/@stdlib/ndarray/base/to-rotl90/docs/types/test.ts
@@ -0,0 +1,76 @@
+/*
+* @license Apache-2.0
+*
+* Copyright (c) 2026 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 zeros = require( '@stdlib/ndarray/base/zeros' );
+import toRotl90 = require( './index' );
+
+
+// TESTS //
+
+// The function returns an ndarray...
+{
+	const sh = [ 2, 2 ];
+	const ord = 'row-major';
+
+	toRotl90( zeros( 'float64', sh, ord ), 1 ); // $ExpectType float64ndarray
+	toRotl90( zeros( 'float32', sh, ord ), 1 ); // $ExpectType float32ndarray
+	toRotl90( zeros( 'complex128', sh, ord ), 1 ); // $ExpectType complex128ndarray
+	toRotl90( zeros( 'complex64', sh, ord ), 1 ); // $ExpectType complex64ndarray
+	toRotl90( zeros( 'int32', sh, ord ), 1 ); // $ExpectType int32ndarray
+	toRotl90( zeros( 'int16', sh, ord ), 1 ); // $ExpectType int16ndarray
+	toRotl90( zeros( 'int8', sh, ord ), 1 ); // $ExpectType int8ndarray
+	toRotl90( zeros( 'uint32', sh, ord ), 1 ); // $ExpectType uint32ndarray
+	toRotl90( zeros( 'uint16', sh, ord ), 1 ); // $ExpectType uint16ndarray
+	toRotl90( zeros( 'uint8', sh, ord ), 1 ); // $ExpectType uint8ndarray
+	toRotl90( zeros( 'uint8c', sh, ord ), 1 ); // $ExpectType uint8cndarray
+	toRotl90( zeros( 'generic', sh, ord ), 1 ); // $ExpectType genericndarray<number>
+}
+
+// The compiler throws an error if the function is provided a first argument which is not an ndarray...
+{
+	toRotl90( '10', 1 ); // $ExpectError
+	toRotl90( 10, 1 ); // $ExpectError
+	toRotl90( false, 1 ); // $ExpectError
+	toRotl90( true, 1 ); // $ExpectError
+	toRotl90( null, 1 ); // $ExpectError
+	toRotl90( void 0, 1 ); // $ExpectError
+	toRotl90( [], 1 ); // $ExpectError
+	toRotl90( {}, 1 ); // $ExpectError
+	toRotl90( ( x: number ): number => x, 1 ); // $ExpectError
+}
+
+// The compiler throws an error if the function is provided a second argument which is not a number...
+{
+	const x = zeros( 'float64', [ 2, 2 ], 'row-major' );
+
+	toRotl90( x, '10' ); // $ExpectError
+	toRotl90( x, false ); // $ExpectError
+	toRotl90( x, true ); // $ExpectError
+	toRotl90( x, null ); // $ExpectError
+	toRotl90( x, void 0 ); // $ExpectError
+	toRotl90( x, [] ); // $ExpectError
+	toRotl90( x, {} ); // $ExpectError
+	toRotl90( x, ( x: number ): number => x ); // $ExpectError
+}
+
+// The compiler throws an error if the function is provided an unsupported number of arguments...
+{
+	toRotl90(); // $ExpectError
+	toRotl90( zeros( 'float64', [ 2, 2 ], 'row-major' ) ); // $ExpectError
+	toRotl90( zeros( 'float64', [ 2, 2 ], 'row-major' ), 1, {} ); // $ExpectError
+}
diff --git a/lib/node_modules/@stdlib/ndarray/base/to-rotl90/examples/index.js b/lib/node_modules/@stdlib/ndarray/base/to-rotl90/examples/index.js
new file mode 100644
index 000000000000..56d85fc1dd32
--- /dev/null
+++ b/lib/node_modules/@stdlib/ndarray/base/to-rotl90/examples/index.js
@@ -0,0 +1,51 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 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 array = require( '@stdlib/ndarray/array' );
+var ndarray2array = require( '@stdlib/ndarray/to-array' );
+var toRotl90 = require( './../lib' );
+
+// Create a 2x3 matrix:
+var x = array( [ [ 1, 2, 3 ], [ 4, 5, 6 ] ] );
+
+// Rotate 90 degrees counterclockwise:
+var y = toRotl90( x, 1 );
+console.log( ndarray2array( y ) );
+// => [ [ 3, 6 ], [ 2, 5 ], [ 1, 4 ] ]
+
+// Rotate 180 degrees:
+y = toRotl90( x, 2 );
+console.log( ndarray2array( y ) );
+// => [ [ 6, 5, 4 ], [ 3, 2, 1 ] ]
+
+// Rotate 270 degrees counterclockwise:
+y = toRotl90( x, 3 );
+console.log( ndarray2array( y ) );
+// => [ [ 4, 1 ], [ 5, 2 ], [ 6, 3 ] ]
+
+// Rotate 360 degrees:
+y = toRotl90( x, 4 );
+console.log( ndarray2array( y ) );
+// => [ [ 1, 2, 3 ], [ 4, 5, 6 ] ]
+
+// Rotate 90 degrees clockwise (equivalent to k=3):
+y = toRotl90( x, -1 );
+console.log( ndarray2array( y ) );
+// => [ [ 4, 1 ], [ 5, 2 ], [ 6, 3 ] ]
diff --git a/lib/node_modules/@stdlib/ndarray/base/to-rotl90/lib/index.js b/lib/node_modules/@stdlib/ndarray/base/to-rotl90/lib/index.js
new file mode 100644
index 000000000000..831e322b3b48
--- /dev/null
+++ b/lib/node_modules/@stdlib/ndarray/base/to-rotl90/lib/index.js
@@ -0,0 +1,44 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 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';
+
+/**
+* Return a new ndarray where a matrix (or a stack of matrices) is rotated 90 degrees counterclockwise.
+*
+* @module @stdlib/ndarray/base/to-rotl90
+*
+* @example
+* var array = require( '@stdlib/ndarray/array' );
+* var toRotl90 = require( '@stdlib/ndarray/base/to-rotl90' );
+*
+* var x = array( [ [ 1, 2 ], [ 3, 4 ] ] );
+* // returns <ndarray>[ [ 1, 2 ], [ 3, 4 ] ]
+*
+* var y = toRotl90( x, 1 );
+* // returns <ndarray>[ [ 2, 4 ], [ 1, 3 ] ]
+*/
+
+// MODULES //
+
+var main = require( './main.js' );
+
+
+// EXPORTS //
+
+module.exports = main;
diff --git a/lib/node_modules/@stdlib/ndarray/base/to-rotl90/lib/main.js b/lib/node_modules/@stdlib/ndarray/base/to-rotl90/lib/main.js
new file mode 100644
index 000000000000..0cb34d183380
--- /dev/null
+++ b/lib/node_modules/@stdlib/ndarray/base/to-rotl90/lib/main.js
@@ -0,0 +1,65 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 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 emptyLike = require( '@stdlib/ndarray/base/empty-like' );
+var rotl90 = require( '@stdlib/ndarray/base/rotl90' );
+var assign = require( '@stdlib/ndarray/base/assign' );
+
+
+// MAIN //
+
+/**
+* Returns a new ndarray where a matrix (or a stack of matrices) is rotated 90 degrees counterclockwise.
+*
+* @param {ndarray} x - input array
+* @param {integer} k - number of times to rotate by 90 degrees
+* @returns {ndarray} output array
+*
+* @example
+* var array = require( '@stdlib/ndarray/array' );
+*
+* var x = array( [ [ 1, 2 ], [ 3, 4 ] ] );
+* // returns <ndarray>[ [ 1, 2 ], [ 3, 4 ] ]
+*
+* var y = toRotl90( x, 1 );
+* // returns <ndarray>[ [ 2, 4 ], [ 1, 3 ] ]
+*/
+function toRotl90( x, k ) {
+	var out;
+	var xr;
+
+	// Create a rotated view of the input ndarray:
+	xr = rotl90( x, k, false );
+
+	// Create an output ndarray having the same shape and data type as the rotated view:
+	out = emptyLike( xr );
+
+	// Assign the elements of the rotated view to the output ndarray:
+	assign( [ xr, out ] );
+
+	return out;
+}
+
+
+// EXPORTS //
+
+module.exports = toRotl90;
diff --git a/lib/node_modules/@stdlib/ndarray/base/to-rotl90/package.json b/lib/node_modules/@stdlib/ndarray/base/to-rotl90/package.json
new file mode 100644
index 000000000000..8e6440d42d9f
--- /dev/null
+++ b/lib/node_modules/@stdlib/ndarray/base/to-rotl90/package.json
@@ -0,0 +1,66 @@
+{
+  "name": "@stdlib/ndarray/base/to-rotl90",
+  "version": "0.0.0",
+  "description": "Return a new ndarray where a matrix (or a stack of matrices) is rotated 90 degrees counterclockwise.",
+  "license": "Apache-2.0",
+  "author": {
+    "name": "The Stdlib Authors",
+    "url": "https://github.com/stdlib-js/stdlib/graphs/contributors"
+  },
+  "contributors": [
+    {
+      "name": "The Stdlib Authors",
+      "url": "https://github.com/stdlib-js/stdlib/graphs/contributors"
+    }
+  ],
+  "main": "./lib",
+  "directories": {
+    "benchmark": "./benchmark",
+    "doc": "./docs",
+    "example": "./examples",
+    "lib": "./lib",
+    "test": "./test"
+  },
+  "types": "./docs/types",
+  "scripts": {},
+  "homepage": "https://github.com/stdlib-js/stdlib",
+  "repository": {
+    "type": "git",
+    "url": "git://github.com/stdlib-js/stdlib.git"
+  },
+  "bugs": {
+    "url": "https://github.com/stdlib-js/stdlib/issues"
+  },
+  "dependencies": {},
+  "devDependencies": {},
+  "engines": {
+    "node": ">=0.10.0",
+    "npm": ">2.7.0"
+  },
+  "os": [
+    "aix",
+    "darwin",
+    "freebsd",
+    "linux",
+    "macos",
+    "openbsd",
+    "sunos",
+    "win32",
+    "windows"
+  ],
+  "keywords": [
+    "stdlib",
+    "stdtypes",
+    "types",
+    "base",
+    "data",
+    "structure",
+    "ndarray",
+    "matrix",
+    "rotate",
+    "rotation",
+    "rotl90",
+    "counterclockwise",
+    "numpy.rot90"
+  ]
+}
diff --git a/lib/node_modules/@stdlib/ndarray/base/to-rotl90/test/test.js b/lib/node_modules/@stdlib/ndarray/base/to-rotl90/test/test.js
new file mode 100644
index 000000000000..6d8e67d45df5
--- /dev/null
+++ b/lib/node_modules/@stdlib/ndarray/base/to-rotl90/test/test.js
@@ -0,0 +1,538 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 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 tape = require( 'tape' );
+var Float64Array = require( '@stdlib/array/float64' );
+var Float32Array = require( '@stdlib/array/float32' );
+var Complex128Array = require( '@stdlib/array/complex128' );
+var Complex64Array = require( '@stdlib/array/complex64' );
+var real = require( '@stdlib/complex/float64/real' );
+var imag = require( '@stdlib/complex/float64/imag' );
+var realf = require( '@stdlib/complex/float32/real' );
+var imagf = require( '@stdlib/complex/float32/imag' );
+var instanceOf = require( '@stdlib/assert/instance-of' );
+var base = require( '@stdlib/ndarray/base/ctor' );
+var ndarray = require( '@stdlib/ndarray/ctor' );
+var array = require( '@stdlib/ndarray/array' );
+var ndarray2array = require( '@stdlib/ndarray/to-array' );
+var getData = require( '@stdlib/ndarray/data-buffer' );
+var getDType = require( '@stdlib/ndarray/dtype' );
+var getOrder = require( '@stdlib/ndarray/order' );
+var getShape = require( '@stdlib/ndarray/shape' );
+var toRotl90 = require( './../lib' );
+
+
+// TESTS //
+
+tape( 'main export is a function', function test( t ) {
+	t.ok( true, __filename );
+	t.strictEqual( typeof toRotl90, 'function', 'main export is a function' );
+	t.end();
+});
+
+tape( 'when provided a zero-dimensional input array, the function returns a new zero-dimensional array', function test( t ) {
+	var actual;
+	var buf;
+	var x;
+
+	buf = new Float64Array( [ 3.14 ] );
+	x = new base( 'float64', buf, [], [ 0 ], 0, 'row-major' );
+
+	actual = toRotl90( x, 1 );
+	t.strictEqual( instanceOf( actual, base ), true, 'returns expected value' );
+	t.deepEqual( getShape( actual ), [], 'returns expected value' );
+	t.strictEqual( String( getDType( actual ) ), String( getDType( x ) ), 'returns expected value' );
+	t.strictEqual( actual.get(), x.get(), 'returns expected value' );
+	t.notEqual( getData( actual ), getData( x ), 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'when provided a one-dimensional input array, the function returns a new one-dimensional array', function test( t ) {
+	var expected;
+	var actual;
+	var buf;
+	var x;
+
+	buf = new Float64Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ] );
+	x = new base( 'float64', buf, [ 6 ], [ 1 ], 0, 'row-major' );
+
+	actual = toRotl90( x, 1 );
+	t.strictEqual( instanceOf( actual, base ), true, 'returns expected value' );
+	t.deepEqual( getShape( actual ), [ 6 ], 'returns expected value' );
+	t.strictEqual( String( getDType( actual ) ), String( getDType( x ) ), 'returns expected value' );
+	t.notEqual( getData( actual ), getData( x ), 'returns expected value' );
+	expected = [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ];
+	t.deepEqual( ndarray2array( actual ), expected, 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'the function returns a new ndarray where a matrix is rotated counterclockwise for all values of k (dtype=float64, base, row-major)', function test( t ) {
+	var expected;
+	var arr;
+	var buf;
+	var x;
+
+	buf = new Float64Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ] );
+	x = new base( 'float64', buf, [ 2, 3 ], [ 3, 1 ], 0, 'row-major' );
+
+	// k=0 (no rotation):
+	arr = toRotl90( x, 0 );
+	t.strictEqual( instanceOf( arr, base ), true, 'returns expected value' );
+	t.strictEqual( String( getDType( arr ) ), String( getDType( x ) ), 'returns expected value' );
+	t.deepEqual( getShape( arr ), [ 2, 3 ], 'returns expected value' );
+	t.notEqual( getData( arr ), getData( x ), 'returns expected value' );
+	t.strictEqual( getOrder( arr ), getOrder( x ), 'returns expected value' );
+	t.notEqual( arr, x, 'returns expected value' );
+	expected = [ [ 1.0, 2.0, 3.0 ], [ 4.0, 5.0, 6.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// k=1 (90 degrees counterclockwise):
+	arr = toRotl90( x, 1 );
+	t.strictEqual( instanceOf( arr, base ), true, 'returns expected value' );
+	t.strictEqual( String( getDType( arr ) ), String( getDType( x ) ), 'returns expected value' );
+	t.deepEqual( getShape( arr ), [ 3, 2 ], 'returns expected value' );
+	t.notEqual( getData( arr ), getData( x ), 'returns expected value' );
+	expected = [ [ 3.0, 6.0 ], [ 2.0, 5.0 ], [ 1.0, 4.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// k=2 (180 degrees):
+	arr = toRotl90( x, 2 );
+	t.strictEqual( instanceOf( arr, base ), true, 'returns expected value' );
+	t.strictEqual( String( getDType( arr ) ), String( getDType( x ) ), 'returns expected value' );
+	t.deepEqual( getShape( arr ), [ 2, 3 ], 'returns expected value' );
+	t.notEqual( getData( arr ), getData( x ), 'returns expected value' );
+	expected = [ [ 6.0, 5.0, 4.0 ], [ 3.0, 2.0, 1.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// k=3 (270 degrees counterclockwise = 90 degrees clockwise):
+	arr = toRotl90( x, 3 );
+	t.strictEqual( instanceOf( arr, base ), true, 'returns expected value' );
+	t.strictEqual( String( getDType( arr ) ), String( getDType( x ) ), 'returns expected value' );
+	t.deepEqual( getShape( arr ), [ 3, 2 ], 'returns expected value' );
+	t.notEqual( getData( arr ), getData( x ), 'returns expected value' );
+	expected = [ [ 4.0, 1.0 ], [ 5.0, 2.0 ], [ 6.0, 3.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'the function returns a new ndarray where a matrix is rotated counterclockwise for all values of k (dtype=float64, base, column-major)', function test( t ) {
+	var expected;
+	var arr;
+	var buf;
+	var x;
+
+	buf = new Float64Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ] );
+	x = new base( 'float64', buf, [ 2, 3 ], [ 1, 2 ], 0, 'column-major' );
+
+	// In column-major with strides [1,2], x = [ [ 1.0, 3.0, 5.0 ], [ 2.0, 4.0, 6.0 ] ]
+
+	// k=1:
+	arr = toRotl90( x, 1 );
+	t.strictEqual( instanceOf( arr, base ), true, 'returns expected value' );
+	t.deepEqual( getShape( arr ), [ 3, 2 ], 'returns expected value' );
+	t.notEqual( getData( arr ), getData( x ), 'returns expected value' );
+	expected = [ [ 5.0, 6.0 ], [ 3.0, 4.0 ], [ 1.0, 2.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// k=2:
+	arr = toRotl90( x, 2 );
+	t.deepEqual( getShape( arr ), [ 2, 3 ], 'returns expected value' );
+	expected = [ [ 6.0, 4.0, 2.0 ], [ 5.0, 3.0, 1.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// k=3:
+	arr = toRotl90( x, 3 );
+	t.deepEqual( getShape( arr ), [ 3, 2 ], 'returns expected value' );
+	expected = [ [ 2.0, 1.0 ], [ 4.0, 3.0 ], [ 6.0, 5.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'the function returns a new ndarray where a matrix is rotated counterclockwise for all values of k (dtype=float64, non-base)', function test( t ) {
+	var expected;
+	var arr;
+	var buf;
+	var x;
+
+	buf = new Float64Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ] );
+	x = array( buf, {
+		'shape': [ 2, 3 ],
+		'dtype': 'float64'
+	});
+
+	// k=0:
+	arr = toRotl90( x, 0 );
+	t.strictEqual( instanceOf( arr, ndarray ), true, 'returns expected value' );
+	t.notEqual( getData( arr ), getData( x ), 'returns expected value' );
+	expected = [ [ 1.0, 2.0, 3.0 ], [ 4.0, 5.0, 6.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// k=1:
+	arr = toRotl90( x, 1 );
+	t.notEqual( getData( arr ), getData( x ), 'returns expected value' );
+	expected = [ [ 3.0, 6.0 ], [ 2.0, 5.0 ], [ 1.0, 4.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// k=2:
+	arr = toRotl90( x, 2 );
+	t.notEqual( getData( arr ), getData( x ), 'returns expected value' );
+	expected = [ [ 6.0, 5.0, 4.0 ], [ 3.0, 2.0, 1.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// k=3:
+	arr = toRotl90( x, 3 );
+	t.notEqual( getData( arr ), getData( x ), 'returns expected value' );
+	expected = [ [ 4.0, 1.0 ], [ 5.0, 2.0 ], [ 6.0, 3.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'the function returns a new ndarray where a matrix is rotated counterclockwise for all values of k (dtype=float32)', function test( t ) {
+	var expected;
+	var arr;
+	var buf;
+	var x;
+
+	buf = new Float32Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ] );
+	x = new base( 'float32', buf, [ 2, 3 ], [ 3, 1 ], 0, 'row-major' );
+
+	// k=1:
+	arr = toRotl90( x, 1 );
+	t.strictEqual( instanceOf( arr, base ), true, 'returns expected value' );
+	t.strictEqual( String( getDType( arr ) ), String( getDType( x ) ), 'returns expected value' );
+	t.deepEqual( getShape( arr ), [ 3, 2 ], 'returns expected value' );
+	t.notEqual( getData( arr ), getData( x ), 'returns expected value' );
+	expected = [ [ 3.0, 6.0 ], [ 2.0, 5.0 ], [ 1.0, 4.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// k=2:
+	arr = toRotl90( x, 2 );
+	t.deepEqual( getShape( arr ), [ 2, 3 ], 'returns expected value' );
+	expected = [ [ 6.0, 5.0, 4.0 ], [ 3.0, 2.0, 1.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// k=3:
+	arr = toRotl90( x, 3 );
+	t.deepEqual( getShape( arr ), [ 3, 2 ], 'returns expected value' );
+	expected = [ [ 4.0, 1.0 ], [ 5.0, 2.0 ], [ 6.0, 3.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// Non-base, k=1:
+	x = array( buf, {
+		'shape': [ 2, 3 ],
+		'dtype': 'float32'
+	});
+	arr = toRotl90( x, 1 );
+	t.notEqual( getData( arr ), getData( x ), 'returns expected value' );
+	expected = [ [ 3.0, 6.0 ], [ 2.0, 5.0 ], [ 1.0, 4.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'the function returns a new ndarray where a matrix is rotated counterclockwise (dtype=complex128, base)', function test( t ) {
+	var arr;
+	var buf;
+	var v;
+	var x;
+
+	buf = new Complex128Array( [ 1.0, 1.0, 2.0, 2.0, 3.0, 3.0, 4.0, 4.0 ] );
+	x = new base( 'complex128', buf, [ 2, 2 ], [ 2, 1 ], 0, 'row-major' );
+
+	// k=1 (90 degrees counterclockwise):
+	arr = toRotl90( x, 1 );
+	t.strictEqual( instanceOf( arr, base ), true, 'returns expected value' );
+	t.strictEqual( String( getDType( arr ) ), String( getDType( x ) ), 'returns expected value' );
+	t.deepEqual( getShape( arr ), [ 2, 2 ], 'returns expected value' );
+	t.notEqual( getData( arr ), getData( x ), 'returns expected value' );
+
+	v = arr.get( 0, 0 );
+	t.strictEqual( real( v ), 2.0, 'returns expected value' );
+	t.strictEqual( imag( v ), 2.0, 'returns expected value' );
+	v = arr.get( 0, 1 );
+	t.strictEqual( real( v ), 4.0, 'returns expected value' );
+	t.strictEqual( imag( v ), 4.0, 'returns expected value' );
+	v = arr.get( 1, 0 );
+	t.strictEqual( real( v ), 1.0, 'returns expected value' );
+	t.strictEqual( imag( v ), 1.0, 'returns expected value' );
+	v = arr.get( 1, 1 );
+	t.strictEqual( real( v ), 3.0, 'returns expected value' );
+	t.strictEqual( imag( v ), 3.0, 'returns expected value' );
+
+	// k=2:
+	arr = toRotl90( x, 2 );
+	v = arr.get( 0, 0 );
+	t.strictEqual( real( v ), 4.0, 'returns expected value' );
+	t.strictEqual( imag( v ), 4.0, 'returns expected value' );
+	v = arr.get( 0, 1 );
+	t.strictEqual( real( v ), 3.0, 'returns expected value' );
+	t.strictEqual( imag( v ), 3.0, 'returns expected value' );
+	v = arr.get( 1, 0 );
+	t.strictEqual( real( v ), 2.0, 'returns expected value' );
+	t.strictEqual( imag( v ), 2.0, 'returns expected value' );
+	v = arr.get( 1, 1 );
+	t.strictEqual( real( v ), 1.0, 'returns expected value' );
+	t.strictEqual( imag( v ), 1.0, 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'the function returns a new ndarray where a matrix is rotated counterclockwise (dtype=complex64, base)', function test( t ) {
+	var arr;
+	var buf;
+	var v;
+	var x;
+
+	buf = new Complex64Array( [ 1.0, 1.0, 2.0, 2.0, 3.0, 3.0, 4.0, 4.0 ] );
+	x = new base( 'complex64', buf, [ 2, 2 ], [ 2, 1 ], 0, 'row-major' );
+
+	// k=1 (90 degrees counterclockwise):
+	arr = toRotl90( x, 1 );
+	t.strictEqual( instanceOf( arr, base ), true, 'returns expected value' );
+	t.strictEqual( String( getDType( arr ) ), String( getDType( x ) ), 'returns expected value' );
+	t.deepEqual( getShape( arr ), [ 2, 2 ], 'returns expected value' );
+	t.notEqual( getData( arr ), getData( x ), 'returns expected value' );
+
+	v = arr.get( 0, 0 );
+	t.strictEqual( realf( v ), 2.0, 'returns expected value' );
+	t.strictEqual( imagf( v ), 2.0, 'returns expected value' );
+	v = arr.get( 0, 1 );
+	t.strictEqual( realf( v ), 4.0, 'returns expected value' );
+	t.strictEqual( imagf( v ), 4.0, 'returns expected value' );
+	v = arr.get( 1, 0 );
+	t.strictEqual( realf( v ), 1.0, 'returns expected value' );
+	t.strictEqual( imagf( v ), 1.0, 'returns expected value' );
+	v = arr.get( 1, 1 );
+	t.strictEqual( realf( v ), 3.0, 'returns expected value' );
+	t.strictEqual( imagf( v ), 3.0, 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'the function returns a new ndarray where a matrix is rotated counterclockwise for all values of k (dtype=generic)', function test( t ) {
+	var expected;
+	var arr;
+	var buf;
+	var x;
+
+	buf = [ 1, 2, 3, 4, 5, 6 ];
+	x = new base( 'generic', buf, [ 2, 3 ], [ 3, 1 ], 0, 'row-major' );
+
+	// k=0:
+	arr = toRotl90( x, 0 );
+	t.strictEqual( instanceOf( arr, base ), true, 'returns expected value' );
+	t.notEqual( getData( arr ), getData( x ), 'returns expected value' );
+	expected = [ [ 1, 2, 3 ], [ 4, 5, 6 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// k=1:
+	arr = toRotl90( x, 1 );
+	t.notEqual( getData( arr ), getData( x ), 'returns expected value' );
+	expected = [ [ 3, 6 ], [ 2, 5 ], [ 1, 4 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// k=2:
+	arr = toRotl90( x, 2 );
+	t.notEqual( getData( arr ), getData( x ), 'returns expected value' );
+	expected = [ [ 6, 5, 4 ], [ 3, 2, 1 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// k=3:
+	arr = toRotl90( x, 3 );
+	t.notEqual( getData( arr ), getData( x ), 'returns expected value' );
+	expected = [ [ 4, 1 ], [ 5, 2 ], [ 6, 3 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// Non-base, k=1:
+	x = array( buf, {
+		'shape': [ 2, 3 ],
+		'dtype': 'generic'
+	});
+	arr = toRotl90( x, 1 );
+	t.notEqual( getData( arr ), getData( x ), 'returns expected value' );
+	expected = [ [ 3, 6 ], [ 2, 5 ], [ 1, 4 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'the function supports negative and large values of k', function test( t ) {
+	var expected;
+	var arr;
+	var buf;
+	var x;
+
+	buf = new Float64Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ] );
+	x = new base( 'float64', buf, [ 2, 3 ], [ 3, 1 ], 0, 'row-major' );
+
+	// k=-1 (90 degrees clockwise):
+	arr = toRotl90( x, -1 );
+	expected = [ [ 4.0, 1.0 ], [ 5.0, 2.0 ], [ 6.0, 3.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// k=-2:
+	arr = toRotl90( x, -2 );
+	expected = [ [ 6.0, 5.0, 4.0 ], [ 3.0, 2.0, 1.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// k=-3:
+	arr = toRotl90( x, -3 );
+	expected = [ [ 3.0, 6.0 ], [ 2.0, 5.0 ], [ 1.0, 4.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// k=-4:
+	arr = toRotl90( x, -4 );
+	expected = [ [ 1.0, 2.0, 3.0 ], [ 4.0, 5.0, 6.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// k=5 (same as k=1):
+	arr = toRotl90( x, 5 );
+	expected = [ [ 3.0, 6.0 ], [ 2.0, 5.0 ], [ 1.0, 4.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// k=8 (same as k=0):
+	arr = toRotl90( x, 8 );
+	expected = [ [ 1.0, 2.0, 3.0 ], [ 4.0, 5.0, 6.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// k=-5 (same as k=-1):
+	arr = toRotl90( x, -5 );
+	expected = [ [ 4.0, 1.0 ], [ 5.0, 2.0 ], [ 6.0, 3.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// k=-8 (same as k=0):
+	arr = toRotl90( x, -8 );
+	expected = [ [ 1.0, 2.0, 3.0 ], [ 4.0, 5.0, 6.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'the function supports a stack of matrices for all values of k', function test( t ) {
+	var expected;
+	var arr;
+	var buf;
+	var x;
+
+	buf = [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 ];
+	x = new base( 'generic', buf, [ 2, 2, 3 ], [ 6, 3, 1 ], 0, 'row-major' );
+
+	// k=0:
+	arr = toRotl90( x, 0 );
+	t.deepEqual( getShape( arr ), [ 2, 2, 3 ], 'returns expected value' );
+	t.notEqual( getData( arr ), getData( x ), 'returns expected value' );
+	expected = [
+		[ [ 1, 2, 3 ], [ 4, 5, 6 ] ],
+		[ [ 7, 8, 9 ], [ 10, 11, 12 ] ]
+	];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// k=1:
+	arr = toRotl90( x, 1 );
+	t.deepEqual( getShape( arr ), [ 2, 3, 2 ], 'returns expected value' );
+	t.notEqual( getData( arr ), getData( x ), 'returns expected value' );
+	expected = [
+		[ [ 3, 6 ], [ 2, 5 ], [ 1, 4 ] ],
+		[ [ 9, 12 ], [ 8, 11 ], [ 7, 10 ] ]
+	];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// k=2:
+	arr = toRotl90( x, 2 );
+	t.deepEqual( getShape( arr ), [ 2, 2, 3 ], 'returns expected value' );
+	t.notEqual( getData( arr ), getData( x ), 'returns expected value' );
+	expected = [
+		[ [ 6, 5, 4 ], [ 3, 2, 1 ] ],
+		[ [ 12, 11, 10 ], [ 9, 8, 7 ] ]
+	];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// k=3:
+	arr = toRotl90( x, 3 );
+	t.deepEqual( getShape( arr ), [ 2, 3, 2 ], 'returns expected value' );
+	t.notEqual( getData( arr ), getData( x ), 'returns expected value' );
+	expected = [
+		[ [ 4, 1 ], [ 5, 2 ], [ 6, 3 ] ],
+		[ [ 10, 7 ], [ 11, 8 ], [ 12, 9 ] ]
+	];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'the function supports a non-zero offset', function test( t ) {
+	var expected;
+	var arr;
+	var buf;
+	var x;
+
+	buf = new Float64Array( [ 0.0, 0.0, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ] );
+	x = new base( 'float64', buf, [ 2, 3 ], [ 3, 1 ], 2, 'row-major' );
+
+	// k=0:
+	arr = toRotl90( x, 0 );
+	expected = [ [ 1.0, 2.0, 3.0 ], [ 4.0, 5.0, 6.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// k=1:
+	arr = toRotl90( x, 1 );
+	expected = [ [ 3.0, 6.0 ], [ 2.0, 5.0 ], [ 1.0, 4.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// k=2:
+	arr = toRotl90( x, 2 );
+	expected = [ [ 6.0, 5.0, 4.0 ], [ 3.0, 2.0, 1.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	// k=3:
+	arr = toRotl90( x, 3 );
+	expected = [ [ 4.0, 1.0 ], [ 5.0, 2.0 ], [ 6.0, 3.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'rotating four times returns the original arrangement', function test( t ) {
+	var expected;
+	var arr;
+	var buf;
+	var x;
+
+	buf = new Float64Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ] );
+	x = new base( 'float64', buf, [ 2, 3 ], [ 3, 1 ], 0, 'row-major' );
+
+	arr = toRotl90( x, 1 );
+	arr = toRotl90( arr, 1 );
+	arr = toRotl90( arr, 1 );
+	arr = toRotl90( arr, 1 );
+
+	expected = [ [ 1.0, 2.0, 3.0 ], [ 4.0, 5.0, 6.0 ] ];
+	t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+	t.notEqual( getData( arr ), getData( x ), 'returns expected value' );
+
+	t.end();
+});