feat: add initial implementation for ndarray/base/unary-reduce-subarray

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Author: kgryte

lib/node_modules/@stdlib/ndarray/base/unary-reduce-subarray/examples/index.js

@@ -0,0 +1,50 @@
+/**
+* @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.
+*/
+
+'use strict';
+
+var discreteUniform = require( '@stdlib/random/array/discrete-uniform' );
+var filled = require( '@stdlib/array/base/filled' );
+var ndarray2array = require( '@stdlib/ndarray/base/to-array' );
+var every = require( '@stdlib/ndarray/base/every' );
+var reduceSubarray = require( './../lib' );
+
+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': filled( false, 2 ),
+	'shape': [ 1, 2 ],
+	'strides': [ 2, 1 ],
+	'offset': 0,
+	'order': 'row-major'
+};
+
+reduceSubarray( every, [ x, y ], [ 1 ] );
+
+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 ) );

lib/node_modules/@stdlib/ndarray/base/unary-reduce-subarray/lib/0d.js

@@ -0,0 +1,92 @@
+/**
+* @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.
+*/
+
+'use strict';
+
+// MODULES //
+
+var without = require( '@stdlib/array/base/without' );
+
+
+// MAIN //
+
+/**
+* Performs a reduction over a list of specified dimensions in an input ndarray and assigns results to a provided output ndarray.
+*
+* @private
+* @param {Function} fcn - reduction function
+* @param {Array<Object>} arrays - ndarrays
+* @param {Options} opts - function options
+* @returns {void}
+*
+* @example
+* var Float64Array = require( '@stdlib/array/float64' );
+* var filled = require( '@stdlib/array/base/filled' );
+* var ndarray2array = require( '@stdlib/ndarray/base/to-array' );
+* var base = require( '@stdlib/ndarray/base/every' );
+*
+* // Create data buffers:
+* var xbuf = new Float64Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 0.0, 7.0, 8.0, 9.0, 10.0, 11.0, 12.0 ] );
+* var ybuf = filled( false, 1 );
+*
+* // Define the array shapes:
+* var xsh = [ 2, 2 ];
+* var ysh = [];
+*
+* // Define the array strides:
+* var sx = [ 6, 1 ];
+* var sy = [ 0 ];
+*
+* // 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': 'generic',
+*     'data': ybuf,
+*     'shape': ysh,
+*     'strides': sy,
+*     'offset': oy,
+*     'order': 'row-major'
+* };
+*
+* // Perform a reduction:
+* unary0d( base, [ x, y ], {} );
+*
+* var v = y.data;
+* // returns [ true ]
+*/
+function unary0d( fcn, arrays, opts ) {
+	arrays[1].data[ arrays[1].offset ] = fcn( without( arrays, 1 ), opts );
+}
+
+
+// EXPORTS //
+
+module.exports = unary0d;

lib/node_modules/@stdlib/ndarray/base/unary-reduce-subarray/lib/0d_accessors.js

@@ -0,0 +1,97 @@
+/**
+* @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.
+*/
+
+'use strict';
+
+// MODULES //
+
+var without = require( '@stdlib/array/base/without' );
+
+
+// MAIN //
+
+/**
+* Performs a reduction over a list of specified dimensions in an input ndarray and assigns results to a provided output ndarray.
+*
+* @private
+* @param {Function} fcn - reduction function
+* @param {Array<Object>} arrays - ndarrays
+* @param {Options} opts - function options
+* @returns {void}
+*
+* @example
+* var toAccessorArray = require( '@stdlib/array/base/to-accessor-array' );
+* var accessors = require( '@stdlib/array/base/accessors' );
+* var Float64Array = require( '@stdlib/array/float64' );
+* var filled = require( '@stdlib/array/base/filled' );
+* var ndarray2array = require( '@stdlib/ndarray/base/to-array' );
+* var base = require( '@stdlib/ndarray/base/every' );
+*
+* // Create data buffers:
+* var xbuf = toAccessorArray( new Float64Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 0.0, 7.0, 8.0, 9.0, 10.0, 11.0, 12.0 ] ) );
+* var ybuf = toAccessorArray( filled( false, 1 ) );
+*
+* // Define the array shapes:
+* var xsh = [ 2, 2 ];
+* var ysh = [];
+*
+* // Define the array strides:
+* var sx = [ 6, 1 ];
+* var sy = [ 0 ];
+*
+* // 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',
+*     'accessors': accessors( xbuf ).accessors
+* };
+*
+* // Create an output ndarray-like object:
+* var y = {
+*     'dtype': 'generic',
+*     'data': ybuf,
+*     'shape': ysh,
+*     'strides': sy,
+*     'offset': oy,
+*     'order': 'row-major',
+*     'accessors': accessors( ybuf ).accessors
+* };
+*
+* // Perform a reduction:
+* unary0d( base, [ x, y ], {} );
+*
+* var v = y.data.get( 0 );
+* // returns true
+*/
+function unary0d( fcn, arrays, opts ) {
+	var y = arrays[ 1 ];
+	y.accessors[ 1 ]( y.data, y.offset, fcn( without( arrays, 1 ), opts ) );
+}
+
+
+// EXPORTS //
+
+module.exports = unary0d;

lib/node_modules/@stdlib/ndarray/base/unary-reduce-subarray/lib/1d.js

@@ -0,0 +1,140 @@
+/**
+* @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.
+*/
+
+'use strict';
+
+// MODULES //
+
+var incrementOffsets = require( './increment_offsets.js' );
+var setViewOffsets = require( './set_view_offsets.js' );
+var offsets = require( './offsets.js' );
+
+
+// MAIN //
+
+/**
+* Performs a reduction over an input ndarray and assigns results to a provided output ndarray.
+*
+* @private
+* @param {Function} fcn - reduction function
+* @param {Array<Object>} arrays - ndarrays
+* @param {Array<Object>} views - initialized ndarray-like objects representing sub-array views
+* @param {IntegerArray} strides - loop dimension strides for the input ndarray
+* @param {Options} opts - function options
+* @returns {void}
+*
+* @example
+* var Float64Array = require( '@stdlib/array/float64' );
+* var filled = require( '@stdlib/array/base/filled' );
+* var ndarray2array = require( '@stdlib/ndarray/base/to-array' );
+* var base = require( '@stdlib/ndarray/base/every' );
+*
+* // Create data buffers:
+* var xbuf = new Float64Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 0.0, 7.0, 8.0, 9.0, 10.0, 11.0, 12.0 ] );
+* var ybuf = filled( false, 3 );
+*
+* // Define the array shapes:
+* var xsh = [ 3, 2, 2 ];
+* var ysh = [ 3 ];
+*
+* // Define the array strides:
+* var sx = [ 4, 2, 1 ];
+* var sy = [ 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': 'generic',
+*     'data': ybuf,
+*     'shape': ysh,
+*     'strides': sy,
+*     'offset': oy,
+*     'order': 'row-major'
+* };
+*
+* // Initialize ndarray-like objects representing sub-array views:
+* var views = [
+*     {
+*         'dtype': x.dtype,
+*         'data': x.data,
+*         'shape': [ 2, 2 ],
+*         'strides': [ 2, 1 ],
+*         'offset': x.offset,
+*         'order': x.order
+*     }
+* ];
+*
+* // Perform a reduction:
+* unary1d( base, [ x, y ], views, [ 4 ], {} );
+*
+* var arr = ndarray2array( y.data, y.shape, y.strides, y.offset, y.order );
+* // returns [ true, false, true ]
+*/
+function unary1d( fcn, arrays, views, strides, opts ) {
+	var ybuf;
+	var dv0;
+	var sh;
+	var S0;
+	var iv;
+	var i0;
+	var y;
+	var i;
+
+	// Note on variable naming convention: S#, dv#, i# where # corresponds to the loop number, with `0` being the innermost loop...
+
+	// Resolve the output ndarray and associated shape:
+	y = arrays[ 1 ];
+	sh = y.shape;
+
+	// Extract loop variables for purposes of loop interchange: dimensions and loop offset (pointer) increments...
+	S0 = sh[ 0 ];
+	dv0 = [ strides[0] ];
+	for ( i = 1; i < arrays.length; i++ ) {
+		dv0.push( arrays[i].strides[0] );
+	}
+	// Resolve a list of pointers to the first indexed elements in the respective ndarrays:
+	iv = offsets( arrays );
+
+	// Cache a reference to the output ndarray buffer:
+	ybuf = y.data;
+
+	// Iterate over the non-reduced ndarray dimensions...
+	for ( i0 = 0; i0 < S0; i0++ ) {
+		setViewOffsets( views, iv );
+		ybuf[ iv[1] ] = fcn( views, opts );
+		incrementOffsets( iv, dv0 );
+	}
+}
+
+
+// EXPORTS //
+
+module.exports = unary1d;