diff --git a/lib/node_modules/@stdlib/ndarray/base/rot90/README.md b/lib/node_modules/@stdlib/ndarray/base/rot90/README.md
new file mode 100644
index 000000000000..b8b80a8a72f9
--- /dev/null
+++ b/lib/node_modules/@stdlib/ndarray/base/rot90/README.md
@@ -0,0 +1,153 @@
+
+
+# rot90
+
+> Rotate a matrix (or a stack of matrices) by 90 degrees.
+
+
+
+
+
+
+
+
+
+
+
+## Usage
+
+```javascript
+var rot90 = require( '@stdlib/ndarray/base/rot90' );
+```
+
+#### rot90( x, k, writable )
+
+Rotates a matrix (or a stack of matrices) `x` by 90 degrees.
+
+```javascript
+var array = require( '@stdlib/ndarray/array' );
+
+var x = array( [ [ 1, 2 ], [ 3, 4 ] ] );
+// returns [ [ 1, 2 ], [ 3, 4 ] ]
+
+var y = rot90( x, 1, false );
+// returns [ [ 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.
+- **writable**: boolean indicating whether a returned ndarray should be writable.
+
+
+
+
+
+
+
+
+
+## Notes
+
+- The `writable` parameter **only** applies to ndarray constructors supporting **read-only** instances.
+- The returned ndarray is a **view** of the input ndarray. Accordingly, writing to the original ndarray will **mutate** the returned ndarray and vice versa.
+- If provided an ndarray with fewer than two dimensions, the function returns the input array unchanged.
+
+
+
+
+
+
+
+
+
+## Examples
+
+
+
+```javascript
+var array = require( '@stdlib/ndarray/array' );
+var ndarray2array = require( '@stdlib/ndarray/to-array' );
+var rot90 = require( '@stdlib/ndarray/base/rot90' );
+
+// Create a 2x3 matrix:
+var x = array( [ [ 1, 2, 3 ], [ 4, 5, 6 ] ] );
+
+// Rotate 90 degrees counterclockwise:
+var y = rot90( x, 1, false );
+var arr = ndarray2array( y );
+// returns [ [ 3, 6 ], [ 2, 5 ], [ 1, 4 ] ]
+
+// Rotate 180 degrees:
+y = rot90( x, 2, false );
+arr = ndarray2array( y );
+// returns [ [ 6, 5, 4 ], [ 3, 2, 1 ] ]
+
+// Rotate 270 degrees counterclockwise (equivalent to 90 degrees clockwise):
+y = rot90( x, 3, false );
+arr = ndarray2array( y );
+// returns [ [ 4, 1 ], [ 5, 2 ], [ 6, 3 ] ]
+
+// Rotate 360 degrees (equivalent to no rotation):
+y = rot90( x, 4, false );
+arr = ndarray2array( y );
+// returns [ [ 1, 2, 3 ], [ 4, 5, 6 ] ]
+
+// Rotate 90 degrees clockwise (equivalent to k=-1):
+y = rot90( x, -1, false );
+arr = ndarray2array( y );
+// returns [ [ 4, 1 ], [ 5, 2 ], [ 6, 3 ] ]
+```
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
diff --git a/lib/node_modules/@stdlib/ndarray/base/rot90/benchmark/benchmark.js b/lib/node_modules/@stdlib/ndarray/base/rot90/benchmark/benchmark.js
new file mode 100644
index 000000000000..b2b4e20eee3a
--- /dev/null
+++ b/lib/node_modules/@stdlib/ndarray/base/rot90/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 rot90 = require( './../lib' );
+
+
+// MAIN //
+
+bench( format( '%s::2d,base', pkg ), function benchmark( b ) {
+ var values;
+ var v;
+ 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++ ) {
+ v = rot90( values[ i%values.length ], 1, false );
+ if ( typeof v !== 'object' ) {
+ b.fail( 'should return an ndarray' );
+ }
+ }
+ b.toc();
+ if ( !isndarrayLike( v ) ) {
+ 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 v;
+ 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++ ) {
+ v = rot90( values[ i%values.length ], 1, false );
+ if ( typeof v !== 'object' ) {
+ b.fail( 'should return an ndarray' );
+ }
+ }
+ b.toc();
+ if ( !isndarrayLike( v ) ) {
+ b.fail( 'should return an ndarray' );
+ }
+ b.pass( 'benchmark finished' );
+ b.end();
+});
+
+bench( format( '%s::3d,base', pkg ), function benchmark( b ) {
+ var values;
+ var v;
+ 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++ ) {
+ v = rot90( values[ i%values.length ], 1, false );
+ if ( typeof v !== 'object' ) {
+ b.fail( 'should return an ndarray' );
+ }
+ }
+ b.toc();
+ if ( !isndarrayLike( v ) ) {
+ 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 v;
+ 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++ ) {
+ v = rot90( values[ i%values.length ], 1, false );
+ if ( typeof v !== 'object' ) {
+ b.fail( 'should return an ndarray' );
+ }
+ }
+ b.toc();
+ if ( !isndarrayLike( v ) ) {
+ b.fail( 'should return an ndarray' );
+ }
+ b.pass( 'benchmark finished' );
+ b.end();
+});
+
+bench( format( '%s::4d,base', pkg ), function benchmark( b ) {
+ var values;
+ var v;
+ 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++ ) {
+ v = rot90( values[ i%values.length ], 1, false );
+ if ( typeof v !== 'object' ) {
+ b.fail( 'should return an ndarray' );
+ }
+ }
+ b.toc();
+ if ( !isndarrayLike( v ) ) {
+ 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 v;
+ 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++ ) {
+ v = rot90( values[ i%values.length ], 1, false );
+ if ( typeof v !== 'object' ) {
+ b.fail( 'should return an ndarray' );
+ }
+ }
+ b.toc();
+ if ( !isndarrayLike( v ) ) {
+ b.fail( 'should return an ndarray' );
+ }
+ b.pass( 'benchmark finished' );
+ b.end();
+});
+
+bench( format( '%s::5d,base', pkg ), function benchmark( b ) {
+ var values;
+ var v;
+ 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++ ) {
+ v = rot90( values[ i%values.length ], 1, false );
+ if ( typeof v !== 'object' ) {
+ b.fail( 'should return an ndarray' );
+ }
+ }
+ b.toc();
+ if ( !isndarrayLike( v ) ) {
+ 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 v;
+ 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++ ) {
+ v = rot90( values[ i%values.length ], 1, false );
+ if ( typeof v !== 'object' ) {
+ b.fail( 'should return an ndarray' );
+ }
+ }
+ b.toc();
+ if ( !isndarrayLike( v ) ) {
+ b.fail( 'should return an ndarray' );
+ }
+ b.pass( 'benchmark finished' );
+ b.end();
+});
diff --git a/lib/node_modules/@stdlib/ndarray/base/rot90/docs/repl.txt b/lib/node_modules/@stdlib/ndarray/base/rot90/docs/repl.txt
new file mode 100644
index 000000000000..ba03ac741d6b
--- /dev/null
+++ b/lib/node_modules/@stdlib/ndarray/base/rot90/docs/repl.txt
@@ -0,0 +1,46 @@
+
+{{alias}}( x, k, writable )
+ Rotates a matrix (or a stack of matrices) by 90 degrees.
+
+ Positive values of `k` rotate counterclockwise. Negative values of `k`
+ rotate clockwise.
+
+ The returned ndarray is a *view* of the input ndarray. Accordingly, writing
+ to the original ndarray will mutate the returned ndarray and vice versa.
+
+ The `writable` parameter only applies to ndarray constructors supporting
+ read-only instances.
+
+ If provided an ndarray with fewer than two dimensions, the function returns
+ the input array unchanged.
+
+ Parameters
+ ----------
+ x: ndarray
+ Input array.
+
+ k: integer
+ Number of times to rotate by 90 degrees.
+
+ writable: boolean
+ Boolean indicating whether the returned ndarray should be writable.
+
+ Returns
+ -------
+ out: ndarray
+ Output array.
+
+ Examples
+ --------
+ > var x = {{alias:@stdlib/ndarray/array}}( [ [ 1, 2 ], [ 3, 4 ] ] )
+ [ [ 1, 2 ], [ 3, 4 ] ]
+ > var y = {{alias}}( x, 1, false )
+ [ [ 2, 4 ], [ 1, 3 ] ]
+ > y = {{alias}}( x, 2, false )
+ [ [ 4, 3 ], [ 2, 1 ] ]
+ > y = {{alias}}( x, 3, false )
+ [ [ 3, 1 ], [ 4, 2 ] ]
+
+ See Also
+ --------
+
diff --git a/lib/node_modules/@stdlib/ndarray/base/rot90/docs/types/index.d.ts b/lib/node_modules/@stdlib/ndarray/base/rot90/docs/types/index.d.ts
new file mode 100644
index 000000000000..d9be4b30451a
--- /dev/null
+++ b/lib/node_modules/@stdlib/ndarray/base/rot90/docs/types/index.d.ts
@@ -0,0 +1,97 @@
+/*
+* @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
+
+///
+
+import { ndarray, typedndarray, genericndarray } from '@stdlib/types/ndarray';
+
+/**
+* Rotates a matrix (or a stack of matrices) by 90 degrees.
+*
+* @param x - input array
+* @param k - number of times to rotate by 90 degrees
+* @param writable - boolean indicating whether the returned ndarray should be writable
+* @returns ndarray view
+*
+* @example
+* var array = require( `@stdlib/ndarray/array` );
+*
+* var x = array( [ [ 1, 2 ], [ 3, 4 ] ] );
+* // returns [ [ 1, 2 ], [ 3, 4 ] ]
+*
+* var y = rot90( x, 1, false );
+* // returns [ [ 2, 4 ], [ 1, 3 ] ]
+*/
+declare function rot90 = typedndarray>( x: T, k: number, writable: boolean ): T;
+
+/**
+* Rotates a matrix (or a stack of matrices) by 90 degrees.
+*
+* @param x - input array
+* @param k - number of times to rotate by 90 degrees
+* @param writable - boolean indicating whether the returned ndarray should be writable
+* @returns ndarray view
+*
+* @example
+* var array = require( `@stdlib/ndarray/array` );
+* var ndarray2array = require( `@stdlib/ndarray/to-array` );
+*
+* var x = array( [ [ 1, 2 ], [ 3, 4 ] ], {
+* 'dtype': 'generic'
+* });
+* // returns [ [ 1, 2 ], [ 3, 4 ] ]
+*
+* var y = rot90( x, 1, false );
+* // returns
+*
+* var arr = ndarray2array( y );
+* // returns [ [ 2, 4 ], [ 1, 3 ] ]
+*/
+declare function rot90 = genericndarray>( x: T, k: number, writable: boolean ): T;
+
+/**
+* Rotates a matrix (or a stack of matrices) by 90 degrees.
+*
+* @param x - input array
+* @param k - number of times to rotate by 90 degrees
+* @param writable - boolean indicating whether the returned ndarray should be writable
+* @returns ndarray view
+*
+* @example
+* var array = require( `@stdlib/ndarray/array` );
+* var ndarray2array = require( `@stdlib/ndarray/to-array` );
+*
+* var x = array( [ [ 1, 2 ], [ 3, 4 ] ], {
+* 'dtype': 'generic'
+* });
+* // returns [ [ 1, 2 ], [ 3, 4 ] ]
+*
+* var y = rot90( x, 1, false );
+* // returns
+*
+* var arr = ndarray2array( y );
+* // returns [ [ 2, 4 ], [ 1, 3 ] ]
+*/
+declare function rot90( x: ndarray, k: number, writable: boolean ): ndarray;
+
+
+// EXPORTS //
+
+export = rot90;
diff --git a/lib/node_modules/@stdlib/ndarray/base/rot90/docs/types/test.ts b/lib/node_modules/@stdlib/ndarray/base/rot90/docs/types/test.ts
new file mode 100644
index 000000000000..63f71eb75edb
--- /dev/null
+++ b/lib/node_modules/@stdlib/ndarray/base/rot90/docs/types/test.ts
@@ -0,0 +1,90 @@
+/*
+* @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 rot90 = require( './index' );
+
+
+// TESTS //
+
+// The function returns an ndarray...
+{
+ const sh = [ 2, 2 ];
+ const ord = 'row-major';
+
+ rot90( zeros( 'float64', sh, ord ), 1, false ); // $ExpectType float64ndarray
+ rot90( zeros( 'float32', sh, ord ), 1, false ); // $ExpectType float32ndarray
+ rot90( zeros( 'complex128', sh, ord ), 1, false ); // $ExpectType complex128ndarray
+ rot90( zeros( 'complex64', sh, ord ), 1, false ); // $ExpectType complex64ndarray
+ rot90( zeros( 'int32', sh, ord ), 1, false ); // $ExpectType int32ndarray
+ rot90( zeros( 'int16', sh, ord ), 1, false ); // $ExpectType int16ndarray
+ rot90( zeros( 'int8', sh, ord ), 1, false ); // $ExpectType int8ndarray
+ rot90( zeros( 'uint32', sh, ord ), 1, false ); // $ExpectType uint32ndarray
+ rot90( zeros( 'uint16', sh, ord ), 1, false ); // $ExpectType uint16ndarray
+ rot90( zeros( 'uint8', sh, ord ), 1, false ); // $ExpectType uint8ndarray
+ rot90( zeros( 'uint8c', sh, ord ), 1, false ); // $ExpectType uint8cndarray
+ rot90( zeros( 'generic', sh, ord ), 1, false ); // $ExpectType genericndarray
+}
+
+// The compiler throws an error if the function is provided a first argument which is not an ndarray having a recognized/supported data type...
+{
+ rot90( '10', 1, false ); // $ExpectError
+ rot90( 10, 1, false ); // $ExpectError
+ rot90( false, 1, false ); // $ExpectError
+ rot90( true, 1, false ); // $ExpectError
+ rot90( null, 1, false ); // $ExpectError
+ rot90( void 0, 1, false ); // $ExpectError
+ rot90( [], 1, false ); // $ExpectError
+ rot90( {}, 1, false ); // $ExpectError
+ rot90( ( x: number ): number => x, 1, false ); // $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' );
+
+ rot90( x, '10', false ); // $ExpectError
+ rot90( x, false, false ); // $ExpectError
+ rot90( x, true, false ); // $ExpectError
+ rot90( x, null, false ); // $ExpectError
+ rot90( x, void 0, false ); // $ExpectError
+ rot90( x, [], false ); // $ExpectError
+ rot90( x, {}, false ); // $ExpectError
+ rot90( x, ( x: number ): number => x, false ); // $ExpectError
+}
+
+// The compiler throws an error if the function is provided a third argument which is not a boolean...
+{
+ const x = zeros( 'float64', [ 2, 2 ], 'row-major' );
+
+ rot90( x, 1, '10' ); // $ExpectError
+ rot90( x, 1, 10 ); // $ExpectError
+ rot90( x, 1, null ); // $ExpectError
+ rot90( x, 1, void 0 ); // $ExpectError
+ rot90( x, 1, [] ); // $ExpectError
+ rot90( x, 1, {} ); // $ExpectError
+ rot90( x, 1, ( x: number ): number => x ); // $ExpectError
+}
+
+// The compiler throws an error if the function is provided an unsupported number of arguments...
+{
+ rot90(); // $ExpectError
+ rot90( zeros( 'float64', [ 2, 2 ], 'row-major' ) ); // $ExpectError
+ rot90( zeros( 'float64', [ 2, 2 ], 'row-major' ), 1 ); // $ExpectError
+ rot90( zeros( 'float64', [ 2, 2 ], 'row-major' ), 1, false, {} ); // $ExpectError
+}
diff --git a/lib/node_modules/@stdlib/ndarray/base/rot90/examples/index.js b/lib/node_modules/@stdlib/ndarray/base/rot90/examples/index.js
new file mode 100644
index 000000000000..eec1e6413eed
--- /dev/null
+++ b/lib/node_modules/@stdlib/ndarray/base/rot90/examples/index.js
@@ -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.
+*/
+
+'use strict';
+
+var array = require( '@stdlib/ndarray/array' );
+var ndarray2array = require( '@stdlib/ndarray/to-array' );
+var rot90 = require( './../lib' );
+
+// Create a 2x3 matrix:
+var x = array( [ [ 1, 2, 3 ], [ 4, 5, 6 ] ] );
+
+// Rotate 90 degrees counterclockwise:
+var y = rot90( x, 1, false );
+console.log( ndarray2array( y ) );
+// => [ [ 3, 6 ], [ 2, 5 ], [ 1, 4 ] ]
+
+// Rotate 180 degrees:
+y = rot90( x, 2, false );
+console.log( ndarray2array( y ) );
+// => [ [ 6, 5, 4 ], [ 3, 2, 1 ] ]
+
+// Rotate 270 degrees counterclockwise:
+y = rot90( x, 3, false );
+console.log( ndarray2array( y ) );
+// => [ [ 4, 1 ], [ 5, 2 ], [ 6, 3 ] ]
+
+// Rotate 360 degrees:
+y = rot90( x, 4, false );
+console.log( ndarray2array( y ) );
+// => [ [ 1, 2, 3 ], [ 4, 5, 6 ] ]
diff --git a/lib/node_modules/@stdlib/ndarray/base/rot90/lib/index.js b/lib/node_modules/@stdlib/ndarray/base/rot90/lib/index.js
new file mode 100644
index 000000000000..9659dd12bf36
--- /dev/null
+++ b/lib/node_modules/@stdlib/ndarray/base/rot90/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';
+
+/**
+* Rotate a matrix (or a stack of matrices) by 90 degrees.
+*
+* @module @stdlib/ndarray/base/rot90
+*
+* @example
+* var array = require( '@stdlib/ndarray/array' );
+* var rot90 = require( '@stdlib/ndarray/base/rot90' );
+*
+* var x = array( [ [ 1, 2 ], [ 3, 4 ] ] );
+* // returns [ [ 1, 2 ], [ 3, 4 ] ]
+*
+* var y = rot90( x, 1, false );
+* // returns [ [ 2, 4 ], [ 1, 3 ] ]
+*/
+
+// MODULES //
+
+var main = require( './main.js' );
+
+
+// EXPORTS //
+
+module.exports = main;
diff --git a/lib/node_modules/@stdlib/ndarray/base/rot90/lib/main.js b/lib/node_modules/@stdlib/ndarray/base/rot90/lib/main.js
new file mode 100644
index 000000000000..f9b27953c879
--- /dev/null
+++ b/lib/node_modules/@stdlib/ndarray/base/rot90/lib/main.js
@@ -0,0 +1,102 @@
+/**
+* @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 getDType = require( '@stdlib/ndarray/base/dtype' );
+var getShape = require( '@stdlib/ndarray/base/shape' );
+var getStrides = require( '@stdlib/ndarray/base/strides' );
+var getOffset = require( '@stdlib/ndarray/base/offset' );
+var getOrder = require( '@stdlib/ndarray/base/order' );
+var getData = require( '@stdlib/ndarray/base/data-buffer' );
+
+
+// MAIN //
+
+/**
+* Rotate a matrix (or a stack of matrices) by 90 degrees.
+*
+* @param {ndarray} x - input array
+* @param {integer} k - number of times to rotate by 90 degrees
+* @param {boolean} writable - boolean indicating whether the returned ndarray should be writable
+* @returns {ndarray} ndarray view
+*
+* @example
+* var array = require( '@stdlib/ndarray/array' );
+*
+* var x = array( [ [ 1, 2 ], [ 3, 4 ] ] );
+* // returns [ [ 1, 2 ], [ 3, 4 ] ]
+*
+* var y = rot90( x, 1, false );
+* // returns [ [ 2, 4 ], [ 1, 3 ] ]
+*
+*/
+function rot90( x, k, writable ) {
+ var offset;
+ var nk;
+ var sh;
+ var st;
+ var sm;
+ var sn;
+ var M;
+ var N;
+ var d;
+
+ sh = getShape( x, true );
+ d = sh.length;
+ if ( d < 2 ) {
+ return x;
+ }
+ st = getStrides( x, true );
+ offset = getOffset( x );
+ nk = ( ( k % 4 ) + 4 ) % 4;
+
+ // Cache the original shape and stride values for the last two dimensions:
+ M = sh[ d-2 ];
+ N = sh[ d-1 ];
+ sm = st[ d-2 ];
+ sn = st[ d-1 ];
+
+ if ( nk === 1 ) {
+ sh[ d-2 ] = N;
+ sh[ d-1 ] = M;
+ st[ d-2 ] = -sn;
+ st[ d-1 ] = sm;
+ offset += ( N - 1 ) * sn;
+ } else if ( nk === 2 ) {
+ st[ d-2 ] = -sm;
+ st[ d-1 ] = -sn;
+ offset += ( ( M - 1 ) * sm ) + ( ( N - 1 ) * sn );
+ } else if ( nk === 3 ) {
+ sh[ d-2 ] = N;
+ sh[ d-1 ] = M;
+ st[ d-2 ] = sn;
+ st[ d-1 ] = -sm;
+ offset += ( M - 1 ) * sm;
+ }
+ return new x.constructor( getDType( x ), getData( x ), sh, st, offset, getOrder( x ), { // eslint-disable-line max-len
+ 'readonly': !writable
+ });
+}
+
+
+// EXPORTS //
+
+module.exports = rot90;
diff --git a/lib/node_modules/@stdlib/ndarray/base/rot90/package.json b/lib/node_modules/@stdlib/ndarray/base/rot90/package.json
new file mode 100644
index 000000000000..ec44bc96c7a0
--- /dev/null
+++ b/lib/node_modules/@stdlib/ndarray/base/rot90/package.json
@@ -0,0 +1,66 @@
+{
+ "name": "@stdlib/ndarray/base/rot90",
+ "version": "0.0.0",
+ "description": "Rotate a matrix (or a stack of matrices) by 90 degrees.",
+ "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",
+ "rot90",
+ "view",
+ "numpy.rot90"
+ ]
+}
diff --git a/lib/node_modules/@stdlib/ndarray/base/rot90/test/test.js b/lib/node_modules/@stdlib/ndarray/base/rot90/test/test.js
new file mode 100644
index 000000000000..aa25225b42d1
--- /dev/null
+++ b/lib/node_modules/@stdlib/ndarray/base/rot90/test/test.js
@@ -0,0 +1,548 @@
+/**
+* @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 isReadOnly = require( '@stdlib/ndarray/base/assert/is-read-only' );
+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 getStrides = require( '@stdlib/ndarray/strides' );
+var rot90 = require( './../lib' );
+
+
+// TESTS //
+
+tape( 'main export is a function', function test( t ) {
+ t.ok( true, __filename );
+ t.strictEqual( typeof rot90, 'function', 'main export is a function' );
+ t.end();
+});
+
+tape( 'the function returns the input array unchanged if provided an ndarray having fewer than two dimensions (0d)', function test( t ) {
+ var arr;
+ var x;
+
+ x = new ndarray( 'float64', new Float64Array( [ 5.0 ] ), [], [ 0 ], 0, 'row-major' );
+ arr = rot90( x, 1, false );
+
+ t.strictEqual( arr, x, 'returns expected value' );
+
+ t.end();
+});
+
+tape( 'the function returns the input array unchanged if provided an ndarray having fewer than two dimensions (1d)', function test( t ) {
+ var arr;
+ var x;
+
+ x = new ndarray( 'float64', new Float64Array( [ 1.0, 2.0, 3.0 ] ), [ 3 ], [ 1 ], 0, 'row-major' );
+ arr = rot90( x, 1, false );
+
+ t.strictEqual( arr, x, 'returns expected value' );
+
+ t.end();
+});
+
+tape( 'the function rotates a matrix 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 = rot90( x, 0, false );
+ 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.deepEqual( getStrides( arr ), [ 3, 1 ], 'returns expected value' );
+ t.strictEqual( 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 = rot90( x, 1, false );
+ 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.strictEqual( 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 = rot90( x, 2, false );
+ 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.strictEqual( 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):
+ arr = rot90( x, 3, false );
+ 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.strictEqual( 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 rotates a matrix 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 = rot90( x, 1, false );
+ t.strictEqual( instanceOf( arr, base ), true, 'returns expected value' );
+ t.deepEqual( getShape( arr ), [ 3, 2 ], 'returns expected value' );
+ t.strictEqual( 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 = rot90( x, 2, false );
+ 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 = rot90( x, 3, false );
+ 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 rotates a matrix 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 = rot90( x, 0, false );
+ t.strictEqual( instanceOf( arr, ndarray ), true, 'returns expected value' );
+ t.strictEqual( isReadOnly( arr ), true, 'returns expected value' );
+ t.strictEqual( 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 = rot90( x, 1, false );
+ t.strictEqual( isReadOnly( arr ), true, 'returns expected value' );
+ t.strictEqual( 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 = rot90( x, 2, false );
+ t.strictEqual( isReadOnly( arr ), true, 'returns expected value' );
+ t.strictEqual( 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 = rot90( x, 3, false );
+ t.strictEqual( isReadOnly( arr ), true, 'returns expected value' );
+ t.strictEqual( 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 rotates a matrix for all values of k (dtype=float32, base)', 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 = rot90( x, 1, false );
+ 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.strictEqual( 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 = rot90( x, 2, false );
+ 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 = rot90( x, 3, false );
+ 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' );
+
+ t.end();
+});
+
+tape( 'the function rotates a matrix for all values of k (dtype=float32, non-base)', 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 = array( buf, {
+ 'shape': [ 2, 3 ],
+ 'dtype': 'float32'
+ });
+
+ // k=1:
+ arr = rot90( x, 1, false );
+ t.strictEqual( isReadOnly( arr ), true, '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=1, writable:
+ arr = rot90( x, 1, true );
+ t.strictEqual( isReadOnly( arr ), false, 'returns expected value' );
+
+ t.end();
+});
+
+tape( 'the function rotates a matrix (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:
+ arr = rot90( x, 1, false );
+ 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.strictEqual( 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 = rot90( x, 2, false );
+ 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 rotates a matrix (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:
+ arr = rot90( x, 1, false );
+ 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.strictEqual( 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 rotates a matrix for all values of k (dtype=generic, base)', 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 = rot90( x, 0, false );
+ t.strictEqual( instanceOf( arr, base ), true, 'returns expected value' );
+ t.strictEqual( 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 = rot90( x, 1, false );
+ t.strictEqual( 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 = rot90( x, 2, false );
+ t.strictEqual( 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 = rot90( x, 3, false );
+ t.strictEqual( getData( arr ), getData( x ), 'returns expected value' );
+ expected = [ [ 4, 1 ], [ 5, 2 ], [ 6, 3 ] ];
+ t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+ t.end();
+});
+
+tape( 'the function rotates a matrix for all values of k (dtype=generic, non-base)', function test( t ) {
+ var expected;
+ var arr;
+ var buf;
+ var x;
+
+ buf = [ 1, 2, 3, 4, 5, 6 ];
+ x = array( buf, {
+ 'shape': [ 2, 3 ],
+ 'dtype': 'generic'
+ });
+
+ // k=1:
+ arr = rot90( x, 1, false );
+ t.strictEqual( isReadOnly( arr ), true, 'returns expected value' );
+ t.strictEqual( getData( arr ), getData( x ), 'returns expected value' );
+ expected = [ [ 3, 6 ], [ 2, 5 ], [ 1, 4 ] ];
+ t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+ // k=1, writable:
+ arr = rot90( x, 1, true );
+ t.strictEqual( isReadOnly( arr ), false, 'returns expected value' );
+
+ t.end();
+});
+
+tape( 'the function supports negative 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`````:
+ arr = rot90( x, -1, false );
+ expected = [ [ 4.0, 1.0 ], [ 5.0, 2.0 ], [ 6.0, 3.0 ] ];
+ t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+ // k=-2:
+ arr = rot90( x, -2, false );
+ expected = [ [ 6.0, 5.0, 4.0 ], [ 3.0, 2.0, 1.0 ] ];
+ t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+ // k=-3:
+ arr = rot90( x, -3, false );
+ expected = [ [ 3.0, 6.0 ], [ 2.0, 5.0 ], [ 1.0, 4.0 ] ];
+ t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+
+ // k=-4:
+ arr = rot90( x, -4, false );
+ 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 = rot90( x, 0, false );
+ t.deepEqual( getShape( arr ), [ 2, 2, 3 ], 'returns expected value' );
+ t.strictEqual( 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 = rot90( x, 1, false );
+ t.deepEqual( getShape( arr ), [ 2, 3, 2 ], 'returns expected value' );
+ t.strictEqual( 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 = rot90( x, 2, false );
+ t.deepEqual( getShape( arr ), [ 2, 2, 3 ], 'returns expected value' );
+ t.strictEqual( 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 = rot90( x, 3, false );
+ t.deepEqual( getShape( arr ), [ 2, 3, 2 ], 'returns expected value' );
+ t.strictEqual( 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 the `writable` parameter', function test( t ) {
+ var arr;
+ var buf;
+ var x;
+
+ buf = new Float64Array( [ 1.0, 2.0, 3.0, 4.0 ] );
+ x = array( buf, {
+ 'shape': [ 2, 2 ],
+ 'dtype': 'float64'
+ });
+
+ // k=0:
+ arr = rot90( x, 0, false );
+ t.strictEqual( isReadOnly( arr ), true, 'returns expected value' );
+ arr = rot90( x, 0, true );
+ t.strictEqual( isReadOnly( arr ), false, 'returns expected value' );
+
+ // k=1:
+ arr = rot90( x, 1, false );
+ t.strictEqual( isReadOnly( arr ), true, 'returns expected value' );
+ arr = rot90( x, 1, true );
+ t.strictEqual( isReadOnly( arr ), false, 'returns expected value' );
+
+ // k=2:
+ arr = rot90( x, 2, false );
+ t.strictEqual( isReadOnly( arr ), true, 'returns expected value' );
+ arr = rot90( x, 2, true );
+ t.strictEqual( isReadOnly( arr ), false, 'returns expected value' );
+
+ // k=3:
+ arr = rot90( x, 3, false );
+ t.strictEqual( isReadOnly( arr ), true, 'returns expected value' );
+ arr = rot90( x, 3, true );
+ t.strictEqual( isReadOnly( arr ), false, '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 = rot90( x, 1, false );
+ arr = rot90( arr, 1, false );
+ arr = rot90( arr, 1, false );
+ arr = rot90( arr, 1, false );
+
+ expected = [ [ 1.0, 2.0, 3.0 ], [ 4.0, 5.0, 6.0 ] ];
+ t.deepEqual( ndarray2array( arr ), expected, 'returns expected value' );
+ t.strictEqual( getData( arr ), getData( x ), 'returns expected value' );
+
+ t.end();
+});