time-to-botec

Benchmark sampling in different programming languages
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skewness.js (1295B)

      1 /**
      2 * @license Apache-2.0
      3 *
      4 * Copyright (c) 2018 The Stdlib Authors.
      5 *
      6 * Licensed under the Apache License, Version 2.0 (the "License");
      7 * you may not use this file except in compliance with the License.
      8 * You may obtain a copy of the License at
      9 *
     10 *    http://www.apache.org/licenses/LICENSE-2.0
     11 *
     12 * Unless required by applicable law or agreed to in writing, software
     13 * distributed under the License is distributed on an "AS IS" BASIS,
     14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     15 * See the License for the specific language governing permissions and
     16 * limitations under the License.
     17 */
     18 
     19 'use strict';
     20 
     21 // MODULES //
     22 
     23 var isnan = require( '@stdlib/math/base/assert/is-nan' );
     24 
     25 
     26 // MAIN //
     27 
     28 /**
     29 * Returns the skewness of a Student's t distribution.
     30 *
     31 * @param {NonNegativeNumber} v - degrees of freedom
     32 * @returns {NonNegativeNumber} skewness
     33 *
     34 * @example
     35 * var v = skewness( 9.0 );
     36 * // returns 0.0
     37 *
     38 * @example
     39 * var v = skewness( 4.0 );
     40 * // returns 0.0
     41 *
     42 * @example
     43 * var v = skewness( 0.5 );
     44 * // returns NaN
     45 *
     46 * @example
     47 * var v = skewness( -0.2 );
     48 * // returns NaN
     49 *
     50 * @example
     51 * var v = skewness( NaN );
     52 * // returns NaN
     53 */
     54 function skewness( v ) {
     55 	if ( isnan( v ) || v <= 3.0 ) {
     56 		return NaN;
     57 	}
     58 	return 0.0;
     59 }
     60 
     61 
     62 // EXPORTS //
     63 
     64 module.exports = skewness;