feat: add the JS native files

Author: anandkaranubc

lib/node_modules/@stdlib/stats/base/dists/chi/variance/benchmark/benchmark.native.js

@@ -0,0 +1,67 @@
+/**
+* @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 resolve = require( 'path' ).resolve;
+var bench = require( '@stdlib/bench' );
+var Float64Array = require( '@stdlib/array/float64' );
+var randu = require( '@stdlib/random/base/randu' );
+var isnan = require( '@stdlib/math/base/assert/is-nan' );
+var tryRequire = require( '@stdlib/utils/try-require' );
+var pkg = require( './../package.json' ).name;
+
+
+// VARIABLES //
+
+var variance = tryRequire( resolve( __dirname, './../lib/native.js' ) );
+var opts = {
+	'skip': ( variance instanceof Error )
+};
+
+
+// MAIN //
+
+bench( pkg+'::native', opts, function benchmark( b ) {
+	var len;
+	var k;
+	var y;
+	var i;
+
+	len = 100;
+	k = new Float64Array( len );
+	for ( i = 0; i < len; i++ ) {
+		k[ i ] = ( randu() * 10.0 ) + 0.1; // Ensure k >= 0
+	}
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		y = variance( k[ i % len ] );
+		if ( isnan( y ) ) {
+			b.fail( 'should not return NaN' );
+		}
+	}
+	b.toc();
+	if ( isnan( y ) ) {
+		b.fail( 'should not return NaN' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});

lib/node_modules/@stdlib/stats/base/dists/chi/variance/lib/native.js

@@ -0,0 +1,58 @@
+/**
+* @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 addon = require( './../src/addon.node' );
+
+
+// MAIN //
+
+/**
+* Returns the variance of a chi distribution.
+*
+* @private
+* @param {NonNegativeNumber} k - degrees of freedom
+* @returns {number} variance
+*
+* @example
+* var v = variance( 9.0 );
+* // returns ~0.485
+*
+* @example
+* var v = variance( 1.0 );
+* // returns ~0.363
+*
+* @example
+* var v = variance( -0.2 );
+* // returns NaN
+*
+* @example
+* var v = variance( NaN );
+* // returns NaN
+*/
+function variance( k ) {
+	return addon( k );
+}
+
+
+// EXPORTS //
+
+module.exports = variance;

lib/node_modules/@stdlib/stats/base/dists/chi/variance/test/test.native.js

@@ -0,0 +1,92 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2018 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 resolve = require( 'path' ).resolve;
+var tape = require( 'tape' );
+var tryRequire = require( '@stdlib/utils/try-require' );
+var abs = require( '@stdlib/math/base/special/abs' );
+var NINF = require( '@stdlib/constants/float64/ninf' );
+var EPS = require( '@stdlib/constants/float64/eps' );
+var isnan = require( '@stdlib/math/base/assert/is-nan' );
+
+
+// VARIABLES //
+
+var variance = tryRequire( resolve( __dirname, './../lib/native.js' ) );
+var opts = {
+	'skip': ( variance instanceof Error )
+};
+
+
+// FIXTURES //
+
+var data = require( './fixtures/julia/data.json' );
+
+
+// TESTS //
+
+tape( 'main export is a function', opts, function test( t ) {
+	t.ok( true, __filename );
+	t.strictEqual( typeof variance, 'function', 'main export is a function' );
+	t.end();
+});
+
+tape( 'if provided `NaN` for `k`, the function returns `NaN`', opts, function test( t ) {
+	var v = variance( NaN );
+	t.equal( isnan( v ), true, 'returns NaN' );
+	t.end();
+});
+
+tape( 'if provided a degrees of freedom parameter `k` that is not a nonnegative number, the function returns `NaN`', opts, function test( t ) {
+	var v;
+
+	v = variance( -1.0 );
+	t.equal( isnan( v ), true, 'returns NaN' );
+
+	v = variance( NINF );
+	t.equal( isnan( v ), true, 'returns NaN' );
+
+	t.end();
+});
+
+tape( 'the function returns the variance of a chi distribution', opts, function test( t ) {
+	var expected;
+	var delta;
+	var tol;
+	var k;
+	var i;
+	var y;
+
+	expected = data.expected;
+	k = data.k;
+	for ( i = 0; i < expected.length; i++ ) {
+		y = variance( k[i] );
+		if ( y === expected[i] ) {
+			t.equal( y, expected[i], 'k:'+k[i]+', y: '+y+', expected: '+expected[i] );
+		} else {
+			delta = abs( y - expected[ i ] );
+			tol = 150.0 * EPS * abs( expected[ i ] );
+			t.ok( delta <= tol, 'within tolerance. k: '+k[i]+'. y: '+y+'. E: '+expected[ i ]+'. Δ: '+delta+'. tol: '+tol+'.' );
+		}
+	}
+	t.end();
+});