feat: add ndarray/base/unary-reduce-strided1d-by

lib/node_modules/@stdlib/ndarray/base/unary-reduce-strided1d-by/README.md

@@ -0,0 +1,278 @@
+<!--
+
+@license Apache-2.0
+
+Copyright (c) 2025 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.
+
+-->
+
+# unaryReduceStrided1dBy
+
+> Perform a reduction over a list of specified dimensions in an input ndarray via a one-dimensional strided array reduction function accepting a callback and assign results to a provided output ndarray.
+
+<section class="intro">
+
+</section>
+
+<!-- /.intro -->
+
+<section class="usage">
+
+## Usage
+
+```javascript
+var unaryReduceStrided1dBy = require( '@stdlib/ndarray/base/unary-reduce-strided1d-by' );
+```
+
+#### unaryReduceStrided1dBy( fcn, arrays, dims\[, options], clbk\[, thisArg] )
+
+Performs a reduction over a list of specified dimensions in an input ndarray via a one-dimensional strided array reduction function accepting a callback and assigns results to a provided output ndarray.
+
+<!-- eslint-disable max-len -->
+
+```javascript
+var Float64Array = require( '@stdlib/array/float64' );
+var ndarray2array = require( '@stdlib/ndarray/base/to-array' );
+var maxBy = require( '@stdlib/stats/base/ndarray/max-by' );
+
+// Define a callback function:
+function clbk( value ) {
+    return value * 2.0;
+}
+
+// Create data buffers:
+var xbuf = new Float64Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0, 12.0 ] );
+var ybuf = new Float64Array( [ 0.0, 0.0, 0.0 ] );
+
+// Define the array shapes:
+var xsh = [ 1, 3, 2, 2 ];
+var ysh = [ 1, 3 ];
+
+// Define the array strides:
+var sx = [ 12, 4, 2, 1 ];
+var sy = [ 3, 1 ];
+
+// Define the index offsets:
+var ox = 0;
+var oy = 0;
+
+// Create an input ndarray-like object:
+var x = {
+    'dtype': 'float64',
+    'data': xbuf,
+    'shape': xsh,
+    'strides': sx,
+    'offset': ox,
+    'order': 'row-major'
+};
+
+// Create an output ndarray-like object:
+var y = {
+    'dtype': 'float64',
+    'data': ybuf,
+    'shape': ysh,
+    'strides': sy,
+    'offset': oy,
+    'order': 'row-major'
+};
+
+// Perform a reduction:
+unaryReduceStrided1dBy( maxBy, [ x, y ], [ 2, 3 ], clbk );
+
+var arr = ndarray2array( y.data, y.shape, y.strides, y.offset, y.order );
+// returns [ [ 8.0, 16.0, 24.0 ] ]
+```
+
+The function accepts the following arguments:
+
+-   **fcn**: function which will be applied to a one-dimensional subarray and should reduce the subarray to a single scalar value.
+-   **arrays**: array-like object containing one input ndarray and one output ndarray, followed by any additional ndarray arguments.
+-   **dims**: list of dimensions over which to perform a reduction.
+-   **options**: function options which are passed through to `fcn` (_optional_).
+-   **clbk**: callback function.
+-   **thisArg**: callback execution context (_optional_).
+
+Each provided ndarray should be an object with the following properties:
+
+-   **dtype**: data type.
+-   **data**: data buffer.
+-   **shape**: dimensions.
+-   **strides**: stride lengths.
+-   **offset**: index offset.
+-   **order**: specifies whether an ndarray is row-major (C-style) or column major (Fortran-style).
+
+The invoked callback function is provided the following arguments:
+
+-   **value**: current array element.
+-   **indices**: current array element indices.
+-   **arr**: the input ndarray.
+
+To set the callback execution context, provide a `thisArg`.
+
+<!-- eslint-disable max-len -->
+
+```javascript
+var Float64Array = require( '@stdlib/array/float64' );
+var ndarray2array = require( '@stdlib/ndarray/base/to-array' );
+var maxBy = require( '@stdlib/stats/base/ndarray/max-by' );
+
+// Define a callback function:
+function clbk( value ) {
+    this.count += 1;
+    return value * 2.0;
+}
+
+// Create data buffers:
+var xbuf = new Float64Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0, 12.0 ] );
+var ybuf = new Float64Array( [ 0.0, 0.0, 0.0 ] );
+
+// Define the array shapes:
+var xsh = [ 1, 3, 2, 2 ];
+var ysh = [ 1, 3 ];
+
+// Define the array strides:
+var sx = [ 12, 4, 2, 1 ];
+var sy = [ 3, 1 ];
+
+// Define the index offsets:
+var ox = 0;
+var oy = 0;
+
+// Create an input ndarray-like object:
+var x = {
+    'dtype': 'float64',
+    'data': xbuf,
+    'shape': xsh,
+    'strides': sx,
+    'offset': ox,
+    'order': 'row-major'
+};
+
+// Create an output ndarray-like object:
+var y = {
+    'dtype': 'float64',
+    'data': ybuf,
+    'shape': ysh,
+    'strides': sy,
+    'offset': oy,
+    'order': 'row-major'
+};
+
+// Define callback execution context:
+var ctx = {
+    'count': 0
+};
+
+// Perform a reduction:
+unaryReduceStrided1dBy( maxBy, [ x, y ], [ 2, 3 ], clbk, ctx );
+
+var arr = ndarray2array( y.data, y.shape, y.strides, y.offset, y.order );
+// returns [ [ 8.0, 16.0, 24.0 ] ]
+
+var count = ctx.count;
+// returns 12
+```
+
+#### TODO: document factory method
+
+</section>
+
+<!-- /.usage -->
+
+<section class="notes">
+
+## Notes
+
+-   The output ndarray and any additional ndarray arguments are expected to have the same dimensions as the non-reduced dimensions of the input ndarray. When calling the reduction function, any additional ndarray arguments are provided as zero-dimensional ndarray-like objects.
+
+-   The reduction function is expected to have the following signature:
+
+    ```text
+    fcn( arrays[, options], clbk[, thisArg ] )
+    ```
+
+    where
+
+    -   **arrays**: array containing a one-dimensional subarray of the input ndarray and any additional ndarray arguments as zero-dimensional ndarrays.
+    -   **options**: function options (_optional_).
+    -   **clbk**: callback function.
+    -   **thisArg**: callback execution context (_optional_).
+
+-   For very high-dimensional ndarrays which are non-contiguous, one should consider copying the underlying data to contiguous memory before performing a reduction in order to achieve better performance.
+
+</section>
+
+<!-- /.notes -->
+
+<section class="examples">
+
+## Examples
+
+<!-- eslint no-undef: "error" -->
+
+```javascript
+var discreteUniform = require( '@stdlib/random/array/discrete-uniform' );
+var zeros = require( '@stdlib/array/base/zeros' );
+var ndarray2array = require( '@stdlib/ndarray/base/to-array' );
+var maxBy = require( '@stdlib/stats/base/ndarray/max-by' );
+var unaryReduceStrided1dBy = require( '@stdlib/ndarray/base/unary-reduce-strided1d-by' );
+
+function clbk( value ) {
+    return value * 2.0;
+}
+
+var N = 10;
+var x = {
+    'dtype': 'generic',
+    'data': discreteUniform( N, -5, 5, {
+        'dtype': 'generic'
+    }),
+    'shape': [ 1, 5, 2 ],
+    'strides': [ 10, 2, 1 ],
+    'offset': 0,
+    'order': 'row-major'
+};
+var y = {
+    'dtype': 'generic',
+    'data': zeros( 2 ),
+    'shape': [ 1, 5 ],
+    'strides': [ 5, 1 ],
+    'offset': 0,
+    'order': 'row-major'
+};
+
+unaryReduceStrided1dBy( maxBy, [ x, y ], [ 2 ], clbk );
+
+console.log( ndarray2array( x.data, x.shape, x.strides, x.offset, x.order ) );
+console.log( ndarray2array( y.data, y.shape, y.strides, y.offset, y.order ) );
+```
+
+</section>
+
+<!-- /.examples -->
+
+<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->
+
+<section class="related">
+
+</section>
+
+<!-- /.related -->
+
+<section class="links">
+
+</section>
+
+<!-- /.links -->

lib/node_modules/@stdlib/ndarray/base/unary-reduce-strided1d-by/docs/repl.txt

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+
+{{alias}}( fcn, arrays, dims[, options], clbk[, thisArg] )
+    Performs a reduction over a list of specified dimensions in an input ndarray
+    via a one-dimensional strided array reduction function accepting a callback
+    and assigns results to a provided output ndarray.
+
+    Each provided "ndarray" should be an object with the following properties:
+
+    - dtype: data type.
+    - data: data buffer.
+    - shape: dimensions.
+    - strides: stride lengths.
+    - offset: index offset.
+    - order: specifies whether an ndarray is row-major (C-style) or column-major
+    (Fortran-style).
+
+    The output ndarray and any additional ndarray arguments are expected to have
+    the same dimensions as the non-reduced dimensions of the input ndarray. When
+    calling the reduction function, any additional ndarray arguments are
+    provided as zero-dimensional ndarray-like objects.
+
+    Parameters
+    ----------
+    fcn: Function
+        Function which will be applied to a one-dimensional subarray and should
+        reduce the subarray to a single scalar value. The function should have
+        the following signature:
+
+            fcn( arrays[, options], clbk[, thisArg] )
+
+        where
+
+        - arrays: array containing a one-dimensional subarray of the input
+        ndarray and any additional ndarray arguments as zero-dimensional
+        ndarrays.
+        - options: function options.
+        - clbk: callback function.
+        - thisArg: callback execution context.
+
+    arrays: ArrayLikeObject<ndarray>
+        Array-like object containing one input ndarray and one output ndarray,
+        followed by any additional ndarray arguments.
+
+    dims: Array<integer>
+        List of dimensions over which to perform a reduction.
+
+    options: Object (optional)
+        Function options.
+
+    clbk: Function
+        Callback function.
+
+    thisArg: any (optional)
+        Callback execution context.
+
+    Examples
+    --------
+    // Define ndarray data and meta data...
+    > var xbuf = new {{alias:@stdlib/array/float64}}( [ 1.0, 2.0, 3.0, 4.0 ] );
+    > var ybuf = new {{alias:@stdlib/array/float64}}( [ 0.0 ] );
+    > var dtype = 'float64';
+    > var shx = [ 2, 2 ];
+    > var shy = [];
+    > var sx = [ 2, 1 ];
+    > var sy = [ 0 ];
+    > var ox = 0;
+    > var oy = 0;
+    > var order = 'row-major';
+
+    // Define a callback function...
+    > function clbk( value ) { return value * 2.0; };
+
+    // Define a wrapper for a statistical function...
+    > function fcn( arrays, cb, ctx ) {
+    ...    var x = arrays[ 0 ];
+    ...    var N = x.shape[ 0 ];
+    ...    var d = x.data;
+    ...    var s = x.strides[ 0 ];
+    ...    var o = x.offset;
+    ...    return {{alias:@stdlib/stats/base/max-by}}.ndarray( N, d, s, o, cb, ctx );
+    ... };
+
+    // Using minimal ndarray-like objects...
+    > x = {
+    ...     'dtype': dtype,
+    ...     'data': xbuf,
+    ...     'shape': shx,
+    ...     'strides': sx,
+    ...     'offset': ox,
+    ...     'order': order
+    ... };
+    > y = {
+    ...     'dtype': dtype,
+    ...     'data': ybuf,
+    ...     'shape': shy,
+    ...     'strides': sy,
+    ...     'offset': oy,
+    ...     'order': order
+    ... };
+    > {{alias}}( fcn, [ x, y ], [ 0, 1 ], clbk );
+    > y.data
+    <Float64Array>[ 8.0 ]
+
+    See Also
+    --------
+