Skip to content
Merged
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
Original file line number Diff line number Diff line change
@@ -0,0 +1,136 @@
<!--

@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.

-->

# dcartesianPower

> Compute the Cartesian power for a double-precision floating-point ndarray.

<section class="intro">

</section>

<!-- /.intro -->

<section class="usage">

## Usage

```javascript
var dcartesianPower = require( '@stdlib/blas/ext/base/ndarray/dcartesian-power' );
```

#### dcartesianPower( arrays )

Computes the Cartesian power for a double-precision floating-point ndarray.

```javascript
var Float64Vector = require( '@stdlib/ndarray/vector/float64' );
var zeros = require( '@stdlib/ndarray/zeros' );
var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' );

var x = new Float64Vector( [ 1.0, 2.0 ] );
var out = zeros( [ 4, 2 ], {
'dtype': 'float64'
});

var k = scalar2ndarray( 2, {
'dtype': 'generic'
});

var v = dcartesianPower( [ x, out, k ] );
// returns <ndarray>[ [ 1.0, 1.0 ], [ 1.0, 2.0 ], [ 2.0, 1.0 ], [ 2.0, 2.0 ] ]

var bool = ( v === out );
// returns true
```

The function has the following parameters:

- **arrays**: array-like object containing the following ndarrays:

- a one-dimensional input ndarray.
- a two-dimensional output ndarray.
- a zero-dimensional ndarray specifying the power.

</section>

<!-- /.usage -->

<section class="notes">

## Notes

- `k`-tuples are stored as rows in the output matrix, where the `j`-th column contains the `j`-th element of each tuple.
- For an input array of length `N`, the output array should have shape `[N^k, k]`, where `N^k` is the number of rows and `k` is the number of columns.
- If `N <= 0` or `k <= 0`, the function returns the output ndarray unchanged.

</section>

<!-- /.notes -->

<section class="examples">

## Examples

<!-- eslint no-undef: "error" -->

```javascript
var discreteUniform = require( '@stdlib/random/discrete-uniform' );
var zeros = require( '@stdlib/ndarray/zeros' );
var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' );
var ndarray2array = require( '@stdlib/ndarray/to-array' );
var dcartesianPower = require( '@stdlib/blas/ext/base/ndarray/dcartesian-power' );

var opts = {
'dtype': 'float64'
};

var x = discreteUniform( [ 3 ], -50, 50, opts );
console.log( ndarray2array( x ) );

var out = zeros( [ 9, 2 ], opts );

var k = scalar2ndarray( 2, {
'dtype': 'generic'
});

var v = dcartesianPower( [ x, out, k ] );
console.log( ndarray2array( v ) );
```

</section>

<!-- /.examples -->

<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->

<section class="related">

</section>

<!-- /.related -->

<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="links">

</section>

<!-- /.links -->
Original file line number Diff line number Diff line change
@@ -0,0 +1,116 @@
/**
* @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 uniform = require( '@stdlib/random/uniform' );
var zeros = require( '@stdlib/ndarray/zeros' );
var isnan = require( '@stdlib/math/base/assert/is-nan' );
var pow = require( '@stdlib/math/base/special/pow' );
var format = require( '@stdlib/string/format' );
var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' );
var pkg = require( './../package.json' ).name;
var dcartesianPower = require( './../lib' );


// VARIABLES //

var options = {
'dtype': 'float64'
};
var K = 2;


// FUNCTIONS //

/**
* Creates a benchmark function.
*
* @private
* @param {PositiveInteger} len - array length
* @returns {Function} benchmark function
*/
function createBenchmark( len ) {
var out;
var x;
var k;

x = uniform( [ len ], -100.0, 100.0, options );
out = zeros( [ pow( len, K ), K ], options );

k = scalar2ndarray( K, {
'dtype': 'generic'
});

return benchmark;

/**
* Benchmark function.
*
* @private
* @param {Benchmark} b - benchmark instance
*/
function benchmark( b ) {
var v;
var i;

b.tic();
for ( i = 0; i < b.iterations; i++ ) {
v = dcartesianPower( [ x, out, k ] );
if ( typeof v !== 'object' ) {
b.fail( 'should return an ndarray' );
}
}
b.toc();
if ( isnan( v.get( i%pow( len, K ), i%K ) ) ) {
b.fail( 'should not return NaN' );
}
b.pass( 'benchmark finished' );
b.end();
}
}


// MAIN //

/**
* Main execution sequence.
*
* @private
*/
function main() {
var len;
var min;
var max;
var f;
var i;

min = 1; // 10^min
max = 3; // 10^max

for ( i = min; i <= max; i++ ) {
len = pow( 10, i );
f = createBenchmark( len );
bench( format( '%s:len=%d', pkg, len ), f );
}
}

main();
Original file line number Diff line number Diff line change
@@ -0,0 +1,39 @@

{{alias}}( arrays )
Computes the Cartesian power for a double-precision floating-point ndarray.

`k`-tuples are stored as rows in the output matrix, where the `j`-th column
contains the `j`-th element of each tuple.

For an input array of length `N`, the output array should have shape
[N^k, k], where `N^k` is the number of rows and `k` is the number of
columns.

If `N <= 0` or `k <= 0`, the function returns the output ndarray unchanged.

Parameters
----------
arrays: ArrayLikeObject<ndarray>
Array-like object containing the following ndarrays:

- a one-dimensional input ndarray.
- a two-dimensional output ndarray.
- a zero-dimensional ndarray specifying the power.

Returns
-------
out: ndarray
Output ndarray.

Examples
--------
> var x = new {{alias:@stdlib/ndarray/vector/float64}}( [ 1.0, 2.0 ] );
> var out = {{alias:@stdlib/ndarray/zeros}}( [ 4, 2 ], { 'dtype': 'float64' } );
> var k = {{alias:@stdlib/ndarray/from-scalar}}( 2, { 'dtype': 'generic' } );
> {{alias}}( [ x, out, k ] );
> out
<ndarray>[ [ 1.0, 1.0 ], [ 1.0, 2.0 ], [ 2.0, 1.0 ], [ 2.0, 2.0 ] ]

See Also
--------

Original file line number Diff line number Diff line change
@@ -0,0 +1,64 @@
/*
* @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 { float64ndarray, typedndarray } from '@stdlib/types/ndarray';

/**
* Computes the Cartesian power for a double-precision floating-point ndarray.
*
* ## Notes
*
* - The function expects the following ndarrays:
*
* - a one-dimensional input ndarray.
* - a two-dimensional output ndarray.
* - a zero-dimensional ndarray specifying the power.
*
* @param arrays - array-like object containing ndarrays
* @returns output ndarray
*
* @example
* var Float64Vector = require( '@stdlib/ndarray/vector/float64' );
* var zeros = require( '@stdlib/ndarray/zeros' );
* var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' );
*
* var x = new Float64Vector( [ 1.0, 2.0 ] );
* var out = zeros( [ 4, 2 ], {
* 'dtype': 'float64'
* });
*
* var k = scalar2ndarray( 2, {
* 'dtype': 'generic'
* });
*
* var v = dcartesianPower( [ x, out, k ] );
* // returns <ndarray>[ [ 1.0, 1.0 ], [ 1.0, 2.0 ], [ 2.0, 1.0 ], [ 2.0, 2.0 ] ]
*
* var bool = ( v === out );
* // returns true
*/
declare function dcartesianPower( arrays: [ float64ndarray, float64ndarray, typedndarray<number> ] ): float64ndarray;


// EXPORTS //

export = dcartesianPower;
Loading