time-to-botec

Benchmark sampling in different programming languages
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README.md (2200B)

      1 <!--
      2 
      3 @license Apache-2.0
      4 
      5 Copyright (c) 2018 The Stdlib Authors.
      6 
      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
     12 
     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
     17 limitations under the License.
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     19 -->
     20 
     21 # Falling Factorial
     22 
     23 > Compute the [falling factorial][falling-and-rising-factorials].
     24 
     25 <section class="intro">
     26 
     27 </section>
     28 
     29 <!-- /.intro -->
     30 
     31 <section class="usage">
     32 
     33 ## Usage
     34 
     35 ```javascript
     36 var fallingFactorial = require( '@stdlib/math/base/special/falling-factorial' );
     37 ```
     38 
     39 #### fallingFactorial( x, n )
     40 
     41 Evaluates the [falling factorial][falling-and-rising-factorials] of `x` and `n`.
     42 
     43 ```javascript
     44 var v = fallingFactorial( 0.9, 5 );
     45 // returns ~0.644
     46 
     47 v = fallingFactorial( -9.0, 3 );
     48 // returns -990.0
     49 
     50 v = fallingFactorial( 0.0, 2 );
     51 // returns 0.0
     52 
     53 v = fallingFactorial( NaN, 3 );
     54 // returns NaN
     55 
     56 v = fallingFactorial( 5.0, NaN );
     57 // returns NaN
     58 
     59 v = fallingFactorial( NaN, NaN );
     60 // returns NaN
     61 ```
     62 
     63 The function returns `NaN` if not provided a nonnegative integer for `n`.
     64 
     65 ```javascript
     66 var v = fallingFactorial( 2.0, 1.5 );
     67 // returns NaN
     68 
     69 v = fallingFactorial( 3.0, -2 );
     70 // returns NaN
     71 ```
     72 
     73 </section>
     74 
     75 <!-- /.usage -->
     76 
     77 <section class="examples">
     78 
     79 ## Examples
     80 
     81 <!-- eslint no-undef: "error" -->
     82 
     83 ```javascript
     84 var randu = require( '@stdlib/random/base/randu' );
     85 var ceil = require( '@stdlib/math/base/special/ceil' );
     86 var fallingFactorial = require( '@stdlib/math/base/special/falling-factorial' );
     87 
     88 var n;
     89 var x;
     90 var i;
     91 
     92 for ( i = 0; i < 100; i++ ) {
     93     x = ( randu()*40.0 ) - 20.0;
     94     n = ceil( randu()*20.0 );
     95     console.log( 'fallingFactorial(%d,%d) = %d', x, n, fallingFactorial( x, n ) );
     96 }
     97 ```
     98 
     99 </section>
    100 
    101 <!-- /.examples -->
    102 
    103 <section class="links">
    104 
    105 [falling-and-rising-factorials]: https://en.wikipedia.org/wiki/Falling_and_rising_factorials
    106 
    107 </section>
    108 
    109 <!-- /.links -->