time-to-botec

Benchmark sampling in different programming languages
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README.md (2637B)

      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
     10 
     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.
     18 
     19 -->
     20 
     21 # erf
     22 
     23 > [Error function][error-function].
     24 
     25 <section class="intro">
     26 
     27 The [error function][error-function] is defined as
     28 
     29 <!-- <equation class="equation" label="eq:error_function" align="center" raw="\operatorname{erf}(x) = \frac{2}{\sqrt\pi}\int_0^x e^{-t^2}\,\mathrm dt" alt="Error function."> -->
     30 
     31 <div class="equation" align="center" data-raw-text="\operatorname{erf}(x) = \frac{2}{\sqrt\pi}\int_0^x e^{-t^2}\,\mathrm dt" data-equation="eq:error_function">
     32     <img src="https://cdn.jsdelivr.net/gh/stdlib-js/stdlib@bb29798906e119fcb2af99e94b60407a270c9b32/lib/node_modules/@stdlib/math/base/special/erf/docs/img/equation_error_function.svg" alt="Error function.">
     33     <br>
     34 </div>
     35 
     36 <!-- </equation> -->
     37 
     38 </section>
     39 
     40 <!-- /.intro -->
     41 
     42 <section class="usage">
     43 
     44 ## Usage
     45 
     46 ```javascript
     47 var erf = require( '@stdlib/math/base/special/erf' );
     48 ```
     49 
     50 #### erf( x )
     51 
     52 Evaluates the [error function][error-function].
     53 
     54 ```javascript
     55 var y = erf( 2.0 );
     56 // returns ~0.9953
     57 
     58 y = erf( -1.0 );
     59 // returns ~-0.8427
     60 ```
     61 
     62 If provided `NaN`, the function returns `NaN`.
     63 
     64 ```javascript
     65 var y = erf( NaN );
     66 // returns NaN
     67 ```
     68 
     69 The [error function][error-function] is an [odd function][odd-function]; i.e., `erf(-x) = -erf(x)`. Thus, in accordance with the [IEEE 754][ieee754] standard, if provided `-0`, the function returns `-0`.
     70 
     71 ```javascript
     72 var y = erf( -0.0 );
     73 // returns -0.0
     74 ```
     75 
     76 </section>
     77 
     78 <!-- /.usage -->
     79 
     80 <section class="examples">
     81 
     82 ## Examples
     83 
     84 <!-- eslint no-undef: "error" -->
     85 
     86 ```javascript
     87 var linspace = require( '@stdlib/array/linspace' );
     88 var erf = require( '@stdlib/math/base/special/erf' );
     89 
     90 var x = linspace( -10.0, 10.0, 100 );
     91 var y;
     92 var i;
     93 
     94 for ( i = 0; i < x.length; i++ ) {
     95     y = erf( x[ i ] );
     96     console.log( 'x: %d, erf(x): %d', x[ i ], y );
     97 }
     98 ```
     99 
    100 </section>
    101 
    102 <!-- /.examples -->
    103 
    104 <section class="links">
    105 
    106 [error-function]: https://en.wikipedia.org/wiki/Error_function
    107 
    108 [odd-function]: https://en.wikipedia.org/wiki/Even_and_odd_functions
    109 
    110 [ieee754]: https://en.wikipedia.org/wiki/IEEE_754-1985
    111 
    112 </section>
    113 
    114 <!-- /.links -->