From 47f1a9af063ab591ce242b5c861a2a4df47e90b0 Mon Sep 17 00:00:00 2001 From: DivyanshuVorrtex Date: Thu, 8 Jan 2026 03:33:14 +0000 Subject: [PATCH 1/7] feat(variance): add new package to stats/base/variance --- type: pre_commit_static_analysis_report description: Results of running static analysis checks when committing changes. report: - task: lint_filenames status: passed - task: lint_editorconfig status: passed - task: lint_markdown status: passed - task: lint_package_json status: passed - task: lint_repl_help status: passed - task: lint_javascript_src status: passed - task: lint_javascript_cli status: na - task: lint_javascript_examples status: passed - task: lint_javascript_tests status: passed - task: lint_javascript_benchmarks status: passed - task: lint_python status: na - task: lint_r status: na - task: lint_c_src status: na - task: lint_c_examples status: na - task: lint_c_benchmarks status: na - task: lint_c_tests_fixtures status: na - task: lint_shell status: na - task: lint_typescript_declarations status: passed - task: lint_typescript_tests status: passed - task: lint_license_headers status: passed --- --- .../stats/base/ndarray/variance/README.md | 186 ++++++++++++++ .../ndarray/variance/benchmark/benchmark.js | 106 ++++++++ .../docs/img/equation_sample_mean.svg | 43 ++++ .../stats/base/ndarray/variance/docs/repl.txt | 54 +++++ .../ndarray/variance/docs/types/index.d.ts | 52 ++++ .../base/ndarray/variance/docs/types/test.ts | 65 +++++ .../base/ndarray/variance/examples/index.js | 37 +++ .../stats/base/ndarray/variance/lib/index.js | 54 +++++ .../stats/base/ndarray/variance/lib/main.js | 69 ++++++ .../stats/base/ndarray/variance/package.json | 72 ++++++ .../stats/base/ndarray/variance/test/test.js | 227 ++++++++++++++++++ 11 files changed, 965 insertions(+) create mode 100644 lib/node_modules/@stdlib/stats/base/ndarray/variance/README.md create mode 100644 lib/node_modules/@stdlib/stats/base/ndarray/variance/benchmark/benchmark.js create mode 100644 lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/img/equation_sample_mean.svg create mode 100644 lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/repl.txt create mode 100644 lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/types/index.d.ts create mode 100644 lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/types/test.ts create mode 100644 lib/node_modules/@stdlib/stats/base/ndarray/variance/examples/index.js create mode 100644 lib/node_modules/@stdlib/stats/base/ndarray/variance/lib/index.js create mode 100644 lib/node_modules/@stdlib/stats/base/ndarray/variance/lib/main.js create mode 100644 lib/node_modules/@stdlib/stats/base/ndarray/variance/package.json create mode 100644 lib/node_modules/@stdlib/stats/base/ndarray/variance/test/test.js diff --git a/lib/node_modules/@stdlib/stats/base/ndarray/variance/README.md b/lib/node_modules/@stdlib/stats/base/ndarray/variance/README.md new file mode 100644 index 000000000000..d287eaa7ce87 --- /dev/null +++ b/lib/node_modules/@stdlib/stats/base/ndarray/variance/README.md @@ -0,0 +1,186 @@ + + +# variance + +> Calculate the [variance][variance] of a one-dimensional ndarray. + +
+ +The population [variance][variance] of a finite size population of size `N` is given by + + + +```math +\sigma^2 = \frac{1}{N} \sum_{i=0}^{N-1} (x_i - \mu)^2 +``` + + + + + +where the population mean is given by + + + +```math +\mu = \frac{1}{N} \sum_{i=0}^{N-1} x_i +``` + + + + + +Often in the analysis of data, the true population [variance][variance] is not known _a priori_ and must be estimated from a sample drawn from the population distribution. If one attempts to use the formula for the population [variance][variance], the result is biased and yields an **uncorrected sample variance**. To compute a **corrected sample variance** for a sample of size `n`, + + + +```math +s^2 = \frac{1}{n-1} \sum_{i=0}^{n-1} (x_i - \bar{x})^2 +``` + + + + + +where the sample mean is given by + + + +```math +\bar{x} = \frac{1}{n} \sum_{i=0}^{n-1} x_i +``` + + + + + +The use of the term `n-1` is commonly referred to as Bessel's correction. Note, however, that applying Bessel's correction can increase the mean squared error between the sample variance and population variance. Depending on the characteristics of the population distribution, other correction factors (e.g., `n-1.5`, `n+1`, etc) can yield better estimators. + +
+ + + +
+ +## Usage + +```javascript +var variance = require( '@stdlib/stats/base/ndarray/variance' ); +``` + +#### variance( arrays ) + +Computes the [variance][variance] of a one-dimensional ndarray. + +```javascript +var ndarray = require( '@stdlib/ndarray/base/ctor' ); +var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' ); + +var opts = { + 'dtype': 'generic' +}; + +var xbuf = [ 1.0, -2.0, 2.0 ]; +var x = new ndarray( opts.dtype, xbuf, [ 3 ], [ 1 ], 0, 'row-major' ); +var correction = scalar2ndarray( 1.0, opts ); + +var v = variance( [ x, correction ] ); +// returns ~4.3333 +``` + +The function has the following parameters: + +- **arrays**: array-like object containing two elements: a one-dimensional input ndarray and a zero-dimensional ndarray specifying the degrees of freedom adjustment. Providing a non-zero degrees of freedom adjustment has the effect of adjusting the divisor during the calculation of the [variance][variance] according to `N-c` where `N` is the number of elements in the input ndarray and `c` corresponds to the provided degrees of freedom adjustment. When computing the [variance][variance] of a population, setting this parameter to `0` is the standard choice (i.e., the provided array contains data constituting an entire population). When computing the corrected sample [variance][variance], setting this parameter to `1` is the standard choice (i.e., the provided array contains data sampled from a larger population; this is commonly referred to as Bessel's correction). + +
+ + + +
+ +## Notes + +- If provided an empty one-dimensional ndarray, the function returns `NaN`. +- If `N - c` is less than or equal to `0` (where `N` corresponds to the number of elements in the input ndarray and `c` corresponds to the provided degrees of freedom adjustment), the function returns `NaN`. + +
+ + + +
+ +## Examples + + + +```javascript +var discreteUniform = require( '@stdlib/random/array/discrete-uniform' ); +var ndarray = require( '@stdlib/ndarray/base/ctor' ); +var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' ); +var ndarray2array = require( '@stdlib/ndarray/to-array' ); +var variance = require( '@stdlib/stats/base/ndarray/variance' ); + +var opts = { + 'dtype': 'float64' +}; + +var xbuf = discreteUniform( 10, -50, 50, opts ); +var x = new ndarray( opts.dtype, xbuf, [ xbuf.length ], [ 1 ], 0, 'row-major' ); +console.log( ndarray2array( x ) ); + +var correction = scalar2ndarray( 1.0, opts ); +var v = variance( [ x, correction ] ); +console.log( v ); +``` + +
+ + + + + +
+ +
+ + + + + +
+ +[variance]: https://en.wikipedia.org/wiki/Variance + +
+ + diff --git a/lib/node_modules/@stdlib/stats/base/ndarray/variance/benchmark/benchmark.js b/lib/node_modules/@stdlib/stats/base/ndarray/variance/benchmark/benchmark.js new file mode 100644 index 000000000000..797aca9a06a9 --- /dev/null +++ b/lib/node_modules/@stdlib/stats/base/ndarray/variance/benchmark/benchmark.js @@ -0,0 +1,106 @@ +/** +* @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/array/uniform' ); +var isnan = require( '@stdlib/math/base/assert/is-nan' ); +var pow = require( '@stdlib/math/base/special/pow' ); +var ndarray = require( '@stdlib/ndarray/base/ctor' ); +var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' ); +var format = require( '@stdlib/string/format' ); +var pkg = require( './../package.json' ).name; +var variance = require( './../lib' ); + + +// VARIABLES // + +var options = { + 'dtype': 'generic' +}; + + +// FUNCTIONS // + +/** +* Creates a benchmark function. +* +* @private +* @param {PositiveInteger} len - array length +* @returns {Function} benchmark function +*/ +function createBenchmark( len ) { + var correction; + var xbuf; + var x; + + xbuf = uniform( len, -10.0, 10.0, options ); + x = new ndarray( options.dtype, xbuf, [ len ], [ 1 ], 0, 'row-major' ); + correction = scalar2ndarray( 1.0, options ); + + return benchmark; + + function benchmark( b ) { + var v; + var i; + + b.tic(); + for ( i = 0; i < b.iterations; i++ ) { + v = variance( [ x, correction ] ); + if ( isnan( v ) ) { + b.fail( 'should not return NaN' ); + } + } + b.toc(); + if ( isnan( v ) ) { + 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 = 6; // 10^max + + for ( i = min; i <= max; i++ ) { + len = pow( 10, i ); + f = createBenchmark( len ); + bench( format( '%s:len=%d', pkg, len ), f ); + } +} + +main(); diff --git a/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/img/equation_sample_mean.svg b/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/img/equation_sample_mean.svg new file mode 100644 index 000000000000..aea7a5f6687a --- /dev/null +++ b/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/img/equation_sample_mean.svg @@ -0,0 +1,43 @@ + +x overbar equals StartFraction 1 Over n EndFraction sigma-summation Underscript i equals 0 Overscript n minus 1 Endscripts x Subscript i + + + \ No newline at end of file diff --git a/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/repl.txt b/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/repl.txt new file mode 100644 index 000000000000..973f20adf006 --- /dev/null +++ b/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/repl.txt @@ -0,0 +1,54 @@ + +{{alias}}( arrays ) + Computes the standard deviation of a one-dimensional ndarray. + + If provided an empty one-dimensional ndarray, the function returns `NaN`. + + If `N - c` is less than or equal to `0` (where `N` corresponds to the number + of elements in the input ndarray and `c` corresponds to the provided degrees + of freedom adjustment), the function returns `NaN`. + + Parameters + ---------- + arrays: ArrayLikeObject + Array-like object containing two elements: a one-dimensional input + ndarray and a zero-dimensional ndarray specifying the degrees of freedom + adjustment. Providing a non-zero degrees of freedom adjustment has the + effect of adjusting the divisor during the calculation of the standard + deviation according to `N-c` where `N` is the number of elements in the + input ndarray and `c` corresponds to the provided degrees of freedom + adjustment. When computing the standard deviation of a population, + setting this parameter to `0` is the standard choice (i.e., the provided + array contains data constituting an entire population). When computing + the corrected sample standard deviation, setting this parameter to `1` + is the standard choice (i.e., the provided array contains data sampled + from a larger population; this is commonly referred to as Bessel's + correction). + + Returns + ------- + out: number + The standard deviation. + + Examples + -------- + // Create input ndarray: + > var xbuf = [ 1.0, -2.0, 2.0 ]; + > var dt = 'generic'; + > var sh = [ xbuf.length ]; + > var st = [ 1 ]; + > var oo = 0; + > var ord = 'row-major'; + > var x = new {{alias:@stdlib/ndarray/ctor}}( dt, xbuf, sh, st, oo, ord ); + + // Create correction ndarray: + > var opts = { 'dtype': dt }; + > var correction = {{alias:@stdlib/ndarray/from-scalar}}( 1.0, opts ); + + // Compute the variance: + > {{alias}}( [ x, correction ] ) + ~4.3333 + + See Also + -------- + diff --git a/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/types/index.d.ts b/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/types/index.d.ts new file mode 100644 index 000000000000..b8c1ddbd2b89 --- /dev/null +++ b/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/types/index.d.ts @@ -0,0 +1,52 @@ +/* +* @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 { typedndarray } from '@stdlib/types/ndarray'; + +/** +* Computes the variance of a one-dimensional ndarray. +* +* @param arrays - array-like object containing a one-dimensional input ndarray and a zero-dimensional ndarray specifying a degrees of freedom adjustment +* @returns variance +* +* @example +* var ndarray = require( '@stdlib/ndarray/base/ctor' ); +* var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' ); +* var Float64Array = require( '@stdlib/array/float64' ); +* +* var opts = { +* 'dtype': 'float64' +* }; +* +* var xbuf = new Float64Array( [ 1.0, -2.0, 2.0 ] ); +* var x = new ndarray( opts.dtype, xbuf, [ 3 ], [ 1 ], 0, 'row-major' ); +* var correction = scalar2ndarray( 1.0, opts ); +* +* var v = variance( [ x, correction ] ); +* // returns ~4.3333 +*/ +declare function variance = typedndarray>( arrays: [ T, T ] ): number; + + +// EXPORTS // + +export = variance; diff --git a/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/types/test.ts b/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/types/test.ts new file mode 100644 index 000000000000..c08d5651ef73 --- /dev/null +++ b/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/types/test.ts @@ -0,0 +1,65 @@ +/* +* @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. +*/ + +/* eslint-disable space-in-parens */ + +import zeros = require( '@stdlib/ndarray/zeros' ); +import scalar2ndarray = require( '@stdlib/ndarray/from-scalar' ); +import variance = require( './index' ); + + +// TESTS // + +// The function returns a number... +{ + const x = zeros( [ 10 ], { + 'dtype': 'float64' + }); + const correction = scalar2ndarray( 1.0, { + 'dtype': 'float64' + }); + + variance( [ x, correction ] ); // $ExpectType number +} + +// The compiler throws an error if the function is provided a first argument which is not an array of ndarrays... +{ + variance( '10' ); // $ExpectError + variance( 10 ); // $ExpectError + variance( true ); // $ExpectError + variance( false ); // $ExpectError + variance( null ); // $ExpectError + variance( undefined ); // $ExpectError + variance( [] ); // $ExpectError + variance( {} ); // $ExpectError + variance( ( x: number ): number => x ); // $ExpectError +} + +// The compiler throws an error if the function is provided an unsupported number of arguments... +{ + const x = zeros( [ 10 ], { + 'dtype': 'float64' + }); + const correction = scalar2ndarray( 1.0, { + 'dtype': 'float64' + }); + + variance(); // $ExpectError + variance( [ x, correction ], 10 ); // $ExpectError +} + diff --git a/lib/node_modules/@stdlib/stats/base/ndarray/variance/examples/index.js b/lib/node_modules/@stdlib/stats/base/ndarray/variance/examples/index.js new file mode 100644 index 000000000000..f4d9d900e07d --- /dev/null +++ b/lib/node_modules/@stdlib/stats/base/ndarray/variance/examples/index.js @@ -0,0 +1,37 @@ +/** +* @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 discreteUniform = require( '@stdlib/random/array/discrete-uniform' ); +var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' ); +var ndarray = require( '@stdlib/ndarray/base/ctor' ); +var ndarray2array = require( '@stdlib/ndarray/to-array' ); +var variance = require( './../lib' ); + +var opts = { + 'dtype': 'float64' +}; + +var xbuf = discreteUniform( 10, -50, 50, opts ); +var x = new ndarray( opts.dtype, xbuf, [ xbuf.length ], [ 1 ], 0, 'row-major' ); +console.log( ndarray2array( x ) ); + +var correction = scalar2ndarray( 1.0, opts ); +var v = variance( [ x, correction ] ); +console.log( v ); diff --git a/lib/node_modules/@stdlib/stats/base/ndarray/variance/lib/index.js b/lib/node_modules/@stdlib/stats/base/ndarray/variance/lib/index.js new file mode 100644 index 000000000000..c755943770eb --- /dev/null +++ b/lib/node_modules/@stdlib/stats/base/ndarray/variance/lib/index.js @@ -0,0 +1,54 @@ +/** +* @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'; + +/** +* Compute the variance of a one-dimensional ndarray. +* +* @module @stdlib/stats/base/ndarray/variance +* +* @example +* var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' ); +* var ndarray = require( '@stdlib/ndarray/ctor' ); +* var variance = require( '@stdlib/stats/base/ndarray/variance' ); +* +* var opts = { +* 'dtype': 'generic' +* }; +* +* // Define a one-dimensional input ndarray: +* var xbuf = [ 1.0, -2.0, 2.0 ]; +* var x = new ndarray( opts.dtype, xbuf, [ 3 ], [ 1 ], 0, 'row-major' ); +* +* // Specify the degrees of freedom adjustment: +* var correction = scalar2ndarray( 1.0, opts ); +* +* // Compute the variance: +* var v = variance( [ x, correction ] ); +* // returns ~4.3333 +*/ + +// MODULES // + +var main = require( './main.js' ); + + +// EXPORTS // + +module.exports = main; diff --git a/lib/node_modules/@stdlib/stats/base/ndarray/variance/lib/main.js b/lib/node_modules/@stdlib/stats/base/ndarray/variance/lib/main.js new file mode 100644 index 000000000000..eef946b91ee5 --- /dev/null +++ b/lib/node_modules/@stdlib/stats/base/ndarray/variance/lib/main.js @@ -0,0 +1,69 @@ +/** +* @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 numelDimension = require( '@stdlib/ndarray/base/numel-dimension' ); +var getStride = require( '@stdlib/ndarray/base/stride' ); +var getOffset = require( '@stdlib/ndarray/base/offset' ); +var getData = require( '@stdlib/ndarray/base/data-buffer' ); +var ndarraylike2scalar = require( '@stdlib/ndarray/base/ndarraylike2scalar' ); +var strided = require( '@stdlib/stats/strided/variance' ).ndarray; + + +// MAIN // + +/** +* Computes the variance of a one-dimensional ndarray. +* +* @param {ArrayLikeObject} arrays - array-like object containing a one-dimensional input ndarray and a zero-dimensional ndarray specifying a degrees of freedom adjustment +* @returns {number} variance +* +* @example +* var Float64Array = require( '@stdlib/array/float64' ); +* var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' ); +* var ndarray = require( '@stdlib/ndarray/base/ctor' ); +* +* var opts = { +* 'dtype': 'float64' +* }; +* +* var xbuf = new Float64Array( [ 2.0, 1.0, 2.0, -2.0, -2.0, 2.0, 3.0, 4.0 ] ); +* var x = new ndarray( opts.dtype, xbuf, [ 4 ], [ 2 ], 1, 'row-major' ); +* +* var correction = scalar2ndarray( 1.0, opts ); +* +* var v = variance( [ x, correction ] ); +* // returns 6.25 +*/ +function variance( arrays ) { + var correction; + var x; + + x = arrays[ 0 ]; + correction = ndarraylike2scalar( arrays[ 1 ] ); + + return strided( numelDimension( x, 0 ), correction, getData( x ), getStride( x, 0 ), getOffset( x ) ); // eslint-disable-line max-len +} + + +// EXPORTS // + +module.exports = variance; diff --git a/lib/node_modules/@stdlib/stats/base/ndarray/variance/package.json b/lib/node_modules/@stdlib/stats/base/ndarray/variance/package.json new file mode 100644 index 000000000000..4ea38524ebd4 --- /dev/null +++ b/lib/node_modules/@stdlib/stats/base/ndarray/variance/package.json @@ -0,0 +1,72 @@ +{ + "name": "@stdlib/stats/base/ndarray/variance", + "version": "0.0.0", + "description": "Compute the standard deviation of a one-dimensional ndarray.", + "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", + "stdmath", + "statistics", + "stats", + "mathematics", + "math", + "standard deviation", + "variance", + "var", + "deviation", + "dispersion", + "spread", + "sample standard deviation", + "unbiased", + "std", + "ndarray", + "typed", + "array" + ], + "__stdlib__": {} +} diff --git a/lib/node_modules/@stdlib/stats/base/ndarray/variance/test/test.js b/lib/node_modules/@stdlib/stats/base/ndarray/variance/test/test.js new file mode 100644 index 000000000000..3f3abed27ea3 --- /dev/null +++ b/lib/node_modules/@stdlib/stats/base/ndarray/variance/test/test.js @@ -0,0 +1,227 @@ +/** +* @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 isnan = require( '@stdlib/math/base/assert/is-nan' ); +var Float64Array = require( '@stdlib/array/float64' ); +var scalar2ndarray = require( '@stdlib/ndarray/from-scalar' ); +var ndarray = require( '@stdlib/ndarray/base/ctor' ); +var variance = require( './../lib' ); + + +// FUNCTIONS // + +/** +* Returns a one-dimensional ndarray. +* +* @private +* @param {Collection} buffer - underlying data buffer +* @param {NonNegativeInteger} length - number of indexed elements +* @param {integer} stride - stride length +* @param {NonNegativeInteger} offset - index offset +* @returns {ndarray} one-dimensional ndarray +*/ +function vector( buffer, length, stride, offset ) { + return new ndarray( 'float64', buffer, [ length ], [ stride ], offset, 'row-major' ); +} + + +// TESTS // + +tape( 'main export is a function', function test( t ) { + t.ok( true, __filename ); + t.strictEqual( typeof variance, 'function', 'main export is a function' ); + t.end(); +}); + +tape( 'the function has an arity of 1', function test( t ) { + t.strictEqual( variance.length, 1, 'has expected arity' ); + t.end(); +}); + +tape( 'the function calculates the variance of a one-dimensional ndarray', function test( t ) { + var correction; + var expected; + var opts; + var x; + var v; + + opts = { + 'dtype': 'float64' + }; + + x = new Float64Array( [ 1.0, -2.0, -4.0, 5.0, 0.0, 3.0 ] ); + correction = scalar2ndarray( 1.0, opts ); + + v = variance( [ vector( x, x.length, 1, 0 ), correction ] ); + expected = 53.5 / (x.length-1); + t.strictEqual( v, expected, 'returns expected value' ); + + x = new Float64Array( [ -4.0, -5.0 ] ); + correction = scalar2ndarray( 1.0, opts ); + + v = variance( [ vector( x, x.length, 1, 0 ), correction ] ); + expected = 0.5; + t.strictEqual( v, expected, 'returns expected value' ); + + x = new Float64Array( [ NaN ] ); + correction = scalar2ndarray( 1.0, opts ); + + v = variance( [ vector( x, x.length, 1, 0 ), correction ] ); + t.strictEqual( isnan( v ), true, 'returns expected value' ); + + x = new Float64Array( [ NaN, NaN ] ); + correction = scalar2ndarray( 1.0, opts ); + + v = variance( [ vector( x, x.length, 1, 0 ), correction ] ); + t.strictEqual( isnan( v ), true, 'returns expected value' ); + + t.end(); +}); + +tape( 'if provided an empty ndarray, the function returns `NaN`', function test( t ) { + var correction; + var opts; + var x; + var v; + + opts = { + 'dtype': 'float64' + }; + + x = new Float64Array( [] ); + correction = scalar2ndarray( 1.0, opts ); + + v = variance( [ vector( x, 0, 1, 0 ), correction ] ); + t.strictEqual( isnan( v ), true, 'returns expected value' ); + + t.end(); +}); + +tape( 'if provided a correction argument yielding `N-correction` less than or equal to `0`, the function returns `NaN`', function test( t ) { + var correction; + var opts; + var x; + var v; + + opts = { + 'dtype': 'float64' + }; + + x = new Float64Array( [ 1.0 ] ); + correction = scalar2ndarray( 1.0, opts ); + + v = variance( [ vector( x, 1, 1, 0 ), correction ] ); + t.strictEqual( isnan( v ), true, 'returns expected value' ); + + t.end(); +}); + +tape( 'the function supports one-dimensional ndarrays having non-unit strides', function test( t ) { + var correction; + var expected; + var opts; + var x; + var v; + + opts = { + 'dtype': 'float64' + }; + + x = new Float64Array([ + 1.0, // 0 + 2.0, + 2.0, // 1 + -7.0, + -2.0, // 2 + 3.0, + 4.0, // 3 + 2.0 + ]); + correction = scalar2ndarray( 1.0, opts ); + + v = variance( [ vector( x, 4, 2, 0 ), correction ] ); + expected = 6.25; + t.strictEqual( v, expected, 'returns expected value' ); + + t.end(); +}); + +tape( 'the function supports one-dimensional ndarrays having negative strides', function test( t ) { + var correction; + var expected; + var opts; + var x; + var v; + + opts = { + 'dtype': 'float64' + }; + + x = new Float64Array([ + 1.0, // 3 + 2.0, + 2.0, // 2 + -7.0, + -2.0, // 1 + 3.0, + 4.0, // 0 + 2.0 + ]); + correction = scalar2ndarray( 1.0, opts ); + + v = variance( [ vector( x, 4, -2, 6 ), correction ] ); + expected = 6.25; + t.strictEqual( v, expected, 'returns expected value' ); + + t.end(); +}); + +tape( 'the function supports one-dimensional ndarrays having non-zero offsets', function test( t ) { + var correction; + var expected; + var opts; + var x; + var v; + + opts = { + 'dtype': 'float64' + }; + + x = new Float64Array([ + 2.0, + 1.0, // 0 + 2.0, + -2.0, // 1 + -2.0, + 2.0, // 2 + 3.0, + 4.0 // 3 + ]); + correction = scalar2ndarray( 1.0, opts ); + + v = variance( [ vector( x, 4, 2, 1 ), correction ] ); + expected = 6.25; + t.strictEqual( v, expected, 'returns expected value' ); + + t.end(); +}); From 032503b4e227a5af94579da14dacad605ce82c53 Mon Sep 17 00:00:00 2001 From: Divyanshu Date: Thu, 8 Jan 2026 09:44:12 +0530 Subject: [PATCH 2/7] Update package.json Signed-off-by: Divyanshu --- .../@stdlib/stats/base/ndarray/variance/package.json | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lib/node_modules/@stdlib/stats/base/ndarray/variance/package.json b/lib/node_modules/@stdlib/stats/base/ndarray/variance/package.json index 4ea38524ebd4..3bbe3417158b 100644 --- a/lib/node_modules/@stdlib/stats/base/ndarray/variance/package.json +++ b/lib/node_modules/@stdlib/stats/base/ndarray/variance/package.json @@ -1,7 +1,7 @@ { "name": "@stdlib/stats/base/ndarray/variance", "version": "0.0.0", - "description": "Compute the standard deviation of a one-dimensional ndarray.", + "description": "Compute the variance of a one-dimensional ndarray.", "license": "Apache-2.0", "author": { "name": "The Stdlib Authors", From 9b71aeb0a587d0fe5da19422a15a32983fc2e585 Mon Sep 17 00:00:00 2001 From: DivyanshuVorrtex Date: Thu, 8 Jan 2026 04:26:43 +0000 Subject: [PATCH 3/7] fix(bugs): fix bugs in the variance --- type: pre_commit_static_analysis_report description: Results of running static analysis checks when committing changes. report: - task: lint_filenames status: passed - task: lint_editorconfig status: passed - task: lint_markdown status: na - task: lint_package_json status: passed - task: lint_repl_help status: passed - task: lint_javascript_src status: na - task: lint_javascript_cli status: na - task: lint_javascript_examples status: na - task: lint_javascript_tests status: na - task: lint_javascript_benchmarks status: na - task: lint_python status: na - task: lint_r status: na - task: lint_c_src status: na - task: lint_c_examples status: na - task: lint_c_benchmarks status: na - task: lint_c_tests_fixtures status: na - task: lint_shell status: na - task: lint_typescript_declarations status: passed - task: lint_typescript_tests status: na - task: lint_license_headers status: passed --- --- .../stats/base/ndarray/variance/docs/repl.txt | 25 ++++++++----------- .../stats/base/ndarray/variance/package.json | 1 - 2 files changed, 11 insertions(+), 15 deletions(-) diff --git a/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/repl.txt b/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/repl.txt index 973f20adf006..12fa0a64f900 100644 --- a/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/repl.txt +++ b/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/repl.txt @@ -1,6 +1,5 @@ - {{alias}}( arrays ) - Computes the standard deviation of a one-dimensional ndarray. + Computes the variance of a one-dimensional ndarray. If provided an empty one-dimensional ndarray, the function returns `NaN`. @@ -14,21 +13,20 @@ Array-like object containing two elements: a one-dimensional input ndarray and a zero-dimensional ndarray specifying the degrees of freedom adjustment. Providing a non-zero degrees of freedom adjustment has the - effect of adjusting the divisor during the calculation of the standard - deviation according to `N-c` where `N` is the number of elements in the - input ndarray and `c` corresponds to the provided degrees of freedom - adjustment. When computing the standard deviation of a population, - setting this parameter to `0` is the standard choice (i.e., the provided - array contains data constituting an entire population). When computing - the corrected sample standard deviation, setting this parameter to `1` - is the standard choice (i.e., the provided array contains data sampled - from a larger population; this is commonly referred to as Bessel's - correction). + effect of adjusting the divisor during the calculation of the variance + according to `N-c`, where `N` is the number of elements in the input + ndarray and `c` corresponds to the provided degrees of freedom + adjustment. When computing the variance of a population, setting this + parameter to `0` is the standard choice (i.e., the provided array + contains data constituting an entire population). When computing the + corrected sample variance, setting this parameter to `1` is the standard + choice (i.e., the provided array contains data sampled from a larger + population; this is commonly referred to as Bessel's correction). Returns ------- out: number - The standard deviation. + The variance. Examples -------- @@ -51,4 +49,3 @@ See Also -------- - diff --git a/lib/node_modules/@stdlib/stats/base/ndarray/variance/package.json b/lib/node_modules/@stdlib/stats/base/ndarray/variance/package.json index 3bbe3417158b..baca7be624d4 100644 --- a/lib/node_modules/@stdlib/stats/base/ndarray/variance/package.json +++ b/lib/node_modules/@stdlib/stats/base/ndarray/variance/package.json @@ -61,7 +61,6 @@ "deviation", "dispersion", "spread", - "sample standard deviation", "unbiased", "std", "ndarray", From d62aedae8103f940ec4029f5cde15be0f54cad48 Mon Sep 17 00:00:00 2001 From: DivyanshuVorrtex Date: Mon, 12 Jan 2026 15:09:04 +0000 Subject: [PATCH 4/7] style: add structure to repl --- type: pre_commit_static_analysis_report description: Results of running static analysis checks when committing changes. report: - task: lint_filenames status: passed - task: lint_editorconfig status: passed - task: lint_markdown status: na - task: lint_package_json status: na - task: lint_repl_help status: passed - task: lint_javascript_src status: na - task: lint_javascript_cli status: na - task: lint_javascript_examples status: na - task: lint_javascript_tests status: na - task: lint_javascript_benchmarks status: passed - task: lint_python status: na - task: lint_r status: na - task: lint_c_src status: na - task: lint_c_examples status: na - task: lint_c_benchmarks status: na - task: lint_c_tests_fixtures status: na - task: lint_shell status: na - task: lint_typescript_declarations status: passed - task: lint_typescript_tests status: na - task: lint_license_headers status: passed --- --- .../stats/base/ndarray/variance/benchmark/benchmark.js | 6 ++++++ .../@stdlib/stats/base/ndarray/variance/docs/repl.txt | 2 +- 2 files changed, 7 insertions(+), 1 deletion(-) diff --git a/lib/node_modules/@stdlib/stats/base/ndarray/variance/benchmark/benchmark.js b/lib/node_modules/@stdlib/stats/base/ndarray/variance/benchmark/benchmark.js index 797aca9a06a9..8d7e7a4531b7 100644 --- a/lib/node_modules/@stdlib/stats/base/ndarray/variance/benchmark/benchmark.js +++ b/lib/node_modules/@stdlib/stats/base/ndarray/variance/benchmark/benchmark.js @@ -58,6 +58,12 @@ function createBenchmark( len ) { return benchmark; + /** + * Benchmark function. + * + * @private + * @param {Benchmark} b - benchmark instance + */ function benchmark( b ) { var v; var i; diff --git a/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/repl.txt b/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/repl.txt index 12fa0a64f900..a18f7d745391 100644 --- a/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/repl.txt +++ b/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/repl.txt @@ -14,7 +14,7 @@ ndarray and a zero-dimensional ndarray specifying the degrees of freedom adjustment. Providing a non-zero degrees of freedom adjustment has the effect of adjusting the divisor during the calculation of the variance - according to `N-c`, where `N` is the number of elements in the input + according to `N-c` where `N` is the number of elements in the input ndarray and `c` corresponds to the provided degrees of freedom adjustment. When computing the variance of a population, setting this parameter to `0` is the standard choice (i.e., the provided array From d7593307ff26d3321ccb1ca54922d3f9317d3283 Mon Sep 17 00:00:00 2001 From: Divyanshu Date: Mon, 19 Jan 2026 10:27:43 +0530 Subject: [PATCH 5/7] Update test.ts --- .../@stdlib/stats/base/ndarray/variance/docs/types/test.ts | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/types/test.ts b/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/types/test.ts index c08d5651ef73..bea0ed3fbde8 100644 --- a/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/types/test.ts +++ b/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/types/test.ts @@ -61,5 +61,4 @@ import variance = require( './index' ); variance(); // $ExpectError variance( [ x, correction ], 10 ); // $ExpectError -} - +} \ No newline at end of file From 4004776749a03a435a4e9ff73a6da735f974691a Mon Sep 17 00:00:00 2001 From: Divyanshu Date: Mon, 19 Jan 2026 10:32:51 +0530 Subject: [PATCH 6/7] Update test.ts --- .../@stdlib/stats/base/ndarray/variance/docs/types/test.ts | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/types/test.ts b/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/types/test.ts index bea0ed3fbde8..ecd6c591dd88 100644 --- a/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/types/test.ts +++ b/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/types/test.ts @@ -61,4 +61,4 @@ import variance = require( './index' ); variance(); // $ExpectError variance( [ x, correction ], 10 ); // $ExpectError -} \ No newline at end of file +} From fd34c708a894aee6f5f36da9d4c55361fadb213c Mon Sep 17 00:00:00 2001 From: Divyanshu Date: Mon, 19 Jan 2026 13:03:35 +0530 Subject: [PATCH 7/7] Update repl.txt Signed-off-by: Divyanshu --- .../@stdlib/stats/base/ndarray/variance/docs/repl.txt | 1 + 1 file changed, 1 insertion(+) diff --git a/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/repl.txt b/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/repl.txt index a18f7d745391..91895681fda7 100644 --- a/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/repl.txt +++ b/lib/node_modules/@stdlib/stats/base/ndarray/variance/docs/repl.txt @@ -1,3 +1,4 @@ + {{alias}}( arrays ) Computes the variance of a one-dimensional ndarray.