time-to-botec

Benchmark sampling in different programming languages
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README.md (3834B)

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      3 @license Apache-2.0
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      5 Copyright (c) 2018 The Stdlib Authors.
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      7 Licensed under the Apache License, Version 2.0 (the "License");
      8 you may not use this file except in compliance with the License.
      9 You may obtain a copy of the License at
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     11    http://www.apache.org/licenses/LICENSE-2.0
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     13 Unless required by applicable law or agreed to in writing, software
     14 distributed under the License is distributed on an "AS IS" BASIS,
     15 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     16 See the License for the specific language governing permissions and
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     20 
     21 # Kernel Betainc
     22 
     23 > [Incomplete beta function][incomplete-beta-function] and its first derivative.
     24 
     25 <section class="intro">
     26 
     27 </section>
     28 
     29 <!-- /.intro -->
     30 
     31 <section class="usage">
     32 
     33 ## Usage
     34 
     35 ```javascript
     36 var kernelBetainc = require( '@stdlib/math/base/special/kernel-betainc' );
     37 ```
     38 
     39 #### kernelBetainc( x, a, b, regularized, upper )
     40 
     41 Evaluates the [incomplete beta function][incomplete-beta-function] and its first derivative for parameters `x`, `a > 0` and `b > 0`. The `regularized` and `upper` boolean parameters are used to specify whether to evaluate the regularized or non-regularized and the upper or lower incomplete beta functions, respectively.
     42 
     43 ```javascript
     44 var out = kernelBetainc( 0.8, 1.0, 0.3, false, false );
     45 // returns [ ~1.277, ~0.926 ]
     46 
     47 out = kernelBetainc( 0.2, 1.0, 2.0, true, false );
     48 // returns [ 0.36, 1.6 ]
     49 
     50 out = kernelBetainc( 0.2, 1.0, 2.0, true, true );
     51 // returns [ 0.64, 1.6 ]
     52 ```
     53 
     54 If provided `NaN` for `x`, `a`, or `b`, the function returns `[ NaN, NaN ]`.
     55 
     56 ```javascript
     57 var out = kernelBetainc( NaN, 1.0, 1.0, true, true );
     58 // returns [ NaN, NaN ]
     59 
     60 out = kernelBetainc( 0.8, NaN, 1.0, true, true );
     61 // returns [ NaN, NaN ]
     62 
     63 out = kernelBetainc( 0.8, 1.0, NaN, true, true );
     64 // returns [ NaN, NaN ]
     65 ```
     66 
     67 If `x` is outside the interval `[0,1]`, the function returns `[ NaN, NaN ]`.
     68 
     69 ```javascript
     70 var out = kernelBetainc( 1.5, 1.0, 1.0, true, true );
     71 // returns [ NaN, NaN ]
     72 
     73 out = kernelBetainc( -0.5, 1.0, 1.0, true, true );
     74 // returns [ NaN, NaN ]
     75 ```
     76 
     77 If `a` or `b` is negative, the function returns `[ NaN, NaN ]`.
     78 
     79 ```javascript
     80 var out = kernelBetainc( 0.5, -2.0, 2.0, true, true );
     81 // returns [ NaN, NaN ]
     82 
     83 out = kernelBetainc( 0.5, 2.0, -2.0, true, true );
     84 // returns [ NaN, NaN ]
     85 ```
     86 
     87 #### kernelBetainc.assign( x, a, b, regularized, upper, out, stride, offset )
     88 
     89 Evaluates the [incomplete beta function][incomplete-beta-function] and its first derivative for parameters `x`, `a > 0` and `b > 0` and assigns results to a provided output array.
     90 
     91 ```javascript
     92 var Float64Array = require( '@stdlib/array/float64' );
     93 
     94 var out = new Float64Array( 2 );
     95 var v = kernelBetainc.assign( 0.2, 1.0, 2.0, true, true, out, 1, 0 );
     96 // returns <Float64Array>[ 0.64, 1.6 ]
     97 
     98 var bool = ( v === out );
     99 // returns true
    100 ```
    101 
    102 The `offset` parameter specifies the index of the first output array element, and the `stride` parameter specifies the stride length between consecutive output array elements.
    103 
    104 </section>
    105 
    106 <!-- /.usage -->
    107 
    108 <section class="examples">
    109 
    110 ## Examples
    111 
    112 <!-- eslint no-undef: "error" -->
    113 
    114 ```javascript
    115 var randu = require( '@stdlib/random/base/randu' );
    116 var kernelBetainc = require( '@stdlib/math/base/special/kernel-betainc' );
    117 
    118 var out;
    119 var i;
    120 var x;
    121 var a;
    122 var b;
    123 
    124 out = [ 0.0, 0.0 ];
    125 for ( i = 0; i < 100; i++ ) {
    126     x = randu();
    127     a = randu() * 10.0;
    128     b = randu() * 10.0;
    129     kernelBetainc( x, a, b, true, false, out, 1, 0 );
    130     console.log( 'x: %d, \t a: %d, \t b: %d, \t f(x,a,b): %d, \t f^1(x,a,b): %d', x.toFixed( 4 ), a.toFixed( 4 ), b.toFixed( 4 ), out[ 0 ].toFixed( 4 ), out[ 1 ].toFixed( 4 ) );
    131 }
    132 ```
    133 
    134 </section>
    135 
    136 <!-- /.examples -->
    137 
    138 <section class="links">
    139 
    140 [incomplete-beta-function]: https://en.wikipedia.org/wiki/Incomplete_beta_function
    141 
    142 </section>
    143 
    144 <!-- /.links -->