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Add discrete uniform skewness
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‎lib/node_modules/@stdlib/math/base/dists/discrete-uniform/skewness/README.md‎

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# Skewness
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> [Discrete uniform][discrete-uniform-distribution] distribution [skewness][skewness].
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<!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->
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<section class="intro">
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The [skewness][skewness] for a [discrete uniform][discrete-uniform-distribution] random variable with minimum support `a` and maximum support `b` is
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<!-- <equation class="equation" label="eq:discrete_uniform_skewness" align="center" raw="\operatorname{skew}\left( X \right) = 0" alt="Skewness for a discrete uniform distribution."> -->
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<!-- </equation> -->
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</section>
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<!-- /.intro -->
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<!-- Package usage documentation. -->
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<section class="usage">
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## Usage
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```javascript
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var skewness = require( '@stdlib/math/base/dists/discrete-uniform/skewness' );
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```
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#### skewness( a, b )
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Returns the [skewness][skewness] of a [discrete uniform][discrete-uniform-distribution] distribution with parameters `a` (minimum support) and `b` (maximum support).
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```javascript
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var v = skewness( 0, 1 );
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// returns 0.0
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v = skewness( 4, 12 );
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// returns 0.0
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v = skewness( 2, 8 );
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// returns 0.0
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```
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If `a` or `b` is not an integer value, the function returns `NaN`.
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```javascript
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var v = skewness( 0.1, 2 );
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// returns NaN
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v = skewness( 0, 2.2 );
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// returns NaN
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v = skewness( NaN, 2 );
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// returns NaN
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v = skewness( 2, NaN );
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// returns NaN
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```
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If provided `a > b`, the function returns `NaN`.
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```javascript
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var y = skewness( 3, 2 );
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// returns NaN
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y = skewness( -1, -2 );
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// returns NaN
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```
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</section>
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<!-- /.usage -->
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<!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
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<section class="notes">
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</section>
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<!-- /.notes -->
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<!-- Package usage examples. -->
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<section class="examples">
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## Examples
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```javascript
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var randint = require( '@stdlib/math/base/random/discrete-uniform' );
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var skewness = require( '@stdlib/math/base/dists/discrete-uniform/skewness' );
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var randa = randint.factory( 0, 10 );
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var randb = randint.factory();
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var a;
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var b;
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var v;
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var i;
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for ( i = 0; i < 10; i++ ) {
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a = randa();
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b = randb( a, a+randa() );
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v = skewness( a, b );
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console.log( 'a: %d, b: %d, skew(X;a,b): %d', a.toFixed( 4 ), b.toFixed( 4 ), v.toFixed( 4 ) );
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}
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```
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</section>
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<!-- /.examples -->
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<!-- Section to include cited references. If references are included, add a horizontal rule *before* the section. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
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<section class="references">
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</section>
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<!-- /.references -->
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<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
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<section class="links">
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[discrete-uniform-distribution]: https://en.wikipedia.org/wiki/Discrete_uniform_distribution
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[skewness]: https://en.wikipedia.org/wiki/Skewness
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</section>
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<!-- /.links -->

‎lib/node_modules/@stdlib/math/base/dists/discrete-uniform/skewness/benchmark/benchmark.js‎

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'use strict';
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// MODULES //
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var bench = require( '@stdlib/bench' );
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var randu = require( '@stdlib/math/base/random/randu' );
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var round = require( '@stdlib/math/base/special/round' );
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var isnan = require( '@stdlib/math/base/assert/is-nan' );
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var pkg = require( './../package.json' ).name;
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var skewness = require( './../lib' );
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// MAIN //
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bench( pkg, function benchmark( b ) {
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var min;
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var max;
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var y;
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var i;
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b.tic();
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for ( i = 0; i < b.iterations; i++ ) {
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min = round( randu()*10.0 );
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max = round( ( randu()*10.0 ) + min );
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y = skewness( min, max );
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if ( isnan( y ) ) {
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b.fail( 'should not return NaN' );
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}
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}
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b.toc();
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if ( isnan( y ) ) {
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b.fail( 'should not return NaN' );
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}
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b.pass( 'benchmark finished' );
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b.end();
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});

‎lib/node_modules/@stdlib/math/base/dists/discrete-uniform/skewness/docs/repl.txt‎

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{{alias}}( a, b )
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Returns the skewness of a discrete uniform distribution.
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If `a > b`, the function returns `NaN`.
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If `a` or `b` is not an integer value, the function returns `NaN`.
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Parameters
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----------
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a: integer
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Minimum support.
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b: integer
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Maximum support.
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Returns
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-------
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out: number
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Skewness.
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Examples
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--------
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> var v = {{alias}}( -2, 2 )
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0.0
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> v = {{alias}}( 4, 12 )
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0.0
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> v = {{alias}}( 2, 8 )
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0.0
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See Also
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--------
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‎lib/node_modules/@stdlib/math/base/dists/discrete-uniform/skewness/examples/index.js‎

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'use strict';
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var randint = require( '@stdlib/math/base/random/discrete-uniform' );
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var skewness = require( './../lib' );
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var randa = randint.factory( 0, 10 );
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var randb = randint.factory();
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var a;
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var b;
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var v;
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var i;
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for ( i = 0; i < 10; i++ ) {
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a = randa();
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b = randb( a, a+randa() );
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v = skewness( a, b );
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console.log( 'a: %d, b: %d, skew(X;a,b): %d', a.toFixed( 4 ), b.toFixed( 4 ), v.toFixed( 4 ) );
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}
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‎lib/node_modules/@stdlib/math/base/dists/discrete-uniform/skewness/lib/index.js‎

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'use strict';
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/**
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* Discrete uniform distribution skewness.
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*
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* @module @stdlib/math/base/dists/discrete-uniform/skewness
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*
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* @example
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* var skewness = require( '@stdlib/math/base/dists/discrete-uniform/skewness' );
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*
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* var v = skewness( 0, 1 );
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* // returns 0.0
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*
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* v = skewness( 2, 10 );
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* // returns 0.0
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*
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* v = skewness( -10, 10 );
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* // returns 0.0
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*/
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// MODULES //
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var skewness = require( './skewness.js' );
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// EXPORTS //
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module.exports = skewness;

‎lib/node_modules/@stdlib/math/base/dists/discrete-uniform/skewness/lib/skewness.js‎

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'use strict';
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// MODULES //
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var isnan = require( '@stdlib/math/base/assert/is-nan' );
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var isInteger = require( '@stdlib/math/base/assert/is-integer' );
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// MAIN //
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/**
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* Returns the skewness of a discrete uniform distribution.
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*
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* @param {integer} a - minimum support
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* @param {integer} b - maximum support
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* @returns {number} skewness
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*
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* @example
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* var v = skewness( 0, 1 );
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* // returns 0.0
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*
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* @example
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* var v = skewness( -4, 4 );
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* // returns 0.0
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*
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* @example
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* var v = skewness( 0, 10 );
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* // returns 0.0
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*
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* @example
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* var v = skewness( 1, -0.1 );
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* // returns NaN
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*
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* @example
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* var v = skewness( -0.1, 1 );
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* // returns NaN
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*
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* @example
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* var v = skewness( 2, NaN );
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* // returns NaN
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*
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* @example
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* var v = skewness( NaN, 2 );
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* // returns NaN
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*/
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function skewness( a, b ) {
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if (
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isnan( a ) ||
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isnan( b ) ||
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!isInteger( a ) ||
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!isInteger( b ) ||
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a > b
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) {
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return NaN;
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}
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return 0.0;
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} // end FUNCTION skewness()
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// EXPORTS //
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module.exports = skewness;

‎lib/node_modules/@stdlib/math/base/dists/discrete-uniform/skewness/package.json‎

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{
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"name": "@stdlib/math/base/dists/discrete-uniform/skewness",
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"version": "0.0.0",
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"description": "Discrete uniform distribution skewness.",
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"author": {
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"name": "The Stdlib Authors",
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"url": "https://github.com/stdlib-js/stdlib/graphs/contributors"
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},
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"contributors": [
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{
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"name": "The Stdlib Authors",
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"url": "https://github.com/stdlib-js/stdlib/graphs/contributors"
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}
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],
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"scripts": {},
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"main": "./lib",
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"repository": {
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"type": "git",
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"url": "git://github.com/stdlib-js/stdlib.git"
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},
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"homepage": "https://github.com/stdlib-js/stdlib",
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"keywords": [
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"stdlib",
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"stdmath",
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"statistics",
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"stats",
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"distribution",
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"dist",
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"skewness",
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"shape",
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"discrete",
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"probability",
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"prob",
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"uniform"
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],
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"bugs": {
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"url": "https://github.com/stdlib-js/stdlib/issues"
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},
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"dependencies": {},
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"devDependencies": {},
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"engines": {
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"node": ">=0.10.0",
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"npm": ">2.7.0"
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},
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"license": "Apache-2.0"
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}

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