time-to-botec

Benchmark sampling in different programming languages
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README.md (2458B)

      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 # logit
     22 
     23 > Compute the [logit][logit] function.
     24 
     25 <section class="intro">
     26 
     27 The [logit][logit] function is defined as the logarithm of the odds `p / (1-p)`; i.e.,
     28 
     29 <!-- <equation class="equation" label="eq:logit_function" align="center" raw="\operatorname{logit}(p)=\log \left({\frac {p}{1-p}}\right)" alt="Logit function."> -->
     30 
     31 <div class="equation" align="center" data-raw-text="\operatorname{logit}(p)=\log \left({\frac {p}{1-p}}\right)" data-equation="eq:logit_function">
     32     <img src="https://cdn.jsdelivr.net/gh/stdlib-js/stdlib@bb29798906e119fcb2af99e94b60407a270c9b32/lib/node_modules/@stdlib/math/base/special/logit/docs/img/equation_logit_function.svg" alt="Logit function.">
     33     <br>
     34 </div>
     35 
     36 <!-- </equation> -->
     37 
     38 The [logit][logit] function is the inverse of the [standard logistic][standard-logistic] function, sometimes also called the sigmoid function. 
     39 
     40 </section>
     41 
     42 <!-- /.intro -->
     43 
     44 <section class="usage">
     45 
     46 ## Usage
     47 
     48 ```javascript
     49 var logit = require( '@stdlib/math/base/special/logit' );
     50 ```
     51 
     52 #### logit( p )
     53 
     54 Computes the [logit][logit] function.
     55 
     56 ```javascript
     57 var v = logit( 0.2 );
     58 // returns ~-1.386
     59 
     60 v = logit( 0.9 );
     61 // returns ~2.197
     62 ```
     63 
     64 If `p < 0` or `p > 1`, the function returns `NaN`.
     65 
     66 ```javascript
     67 var v = logit( 1.3 );
     68 // returns NaN
     69 
     70 v = logit( -0.2 );
     71 // returns NaN
     72 ```
     73 
     74 </section>
     75 
     76 <!-- /.usage -->
     77 
     78 <section class="examples">
     79 
     80 ## Examples
     81 
     82 <!-- eslint no-undef: "error" -->
     83 
     84 ```javascript
     85 var randu = require( '@stdlib/random/base/randu' );
     86 var logit = require( '@stdlib/math/base/special/logit' );
     87 
     88 var p;
     89 var i;
     90 
     91 for ( i = 0; i < 100; i++ ) {
     92     p = randu();
     93     console.log( 'logit(%d) = %d', p, logit( p ) );
     94 }
     95 ```
     96 
     97 </section>
     98 
     99 <!-- /.examples -->
    100 
    101 <section class="links">
    102 
    103 [logit]: https://en.wikipedia.org/wiki/Logit
    104 
    105 [standard-logistic]: https://en.wikipedia.org/wiki/Logistic_function
    106 
    107 </section>
    108 
    109 <!-- /.links -->