time-to-botec

Benchmark sampling in different programming languages
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README.md (3257B)

      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 # incrgmean
     22 
     23 > Compute a [geometric mean][geometric-mean] incrementally.
     24 
     25 <section class="intro">
     26 
     27 The [geometric mean][geometric-mean] is defined as the nth root of a product of _n_ numbers.
     28 
     29 <!-- <equation class="equation" label="eq:geometric_mean" align="center" raw="\biggl( \prod_{i=0}^{n-1} \biggr)^{\frac{1}{n}} = \sqrt[n]{x_0 x_1 \cdots x_{n-1}}" alt="Equation for the geometric mean."> -->
     30 
     31 <div class="equation" align="center" data-raw-text="\biggl( \prod_{i=0}^{n-1} \biggr)^{\frac{1}{n}} = \sqrt[n]{x_0 x_1 \cdots x_{n-1}}" data-equation="eq:geometric_mean">
     32     <img src="https://cdn.jsdelivr.net/gh/stdlib-js/stdlib@cb802bd5cb07ef925c8a3ce9c34db0fb68040d12/lib/node_modules/@stdlib/stats/incr/gmean/docs/img/equation_geometric_mean.svg" alt="Equation for the geometric mean.">
     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 incrgmean = require( '@stdlib/stats/incr/gmean' );
     48 ```
     49 
     50 #### incrgmean()
     51 
     52 Returns an accumulator `function` which incrementally computes a [geometric mean][geometric-mean].
     53 
     54 ```javascript
     55 var accumulator = incrgmean();
     56 ```
     57 
     58 #### accumulator( \[x] )
     59 
     60 If provided an input value `x`, the accumulator function returns an updated [geometric mean][geometric-mean]. If not provided an input value `x`, the accumulator function returns the current [geometric mean][geometric-mean].
     61 
     62 ```javascript
     63 var accumulator = incrgmean();
     64 
     65 var prod = accumulator( 2.0 );
     66 // returns 2.0
     67 
     68 prod = accumulator( 1.0 );
     69 // returns ~1.414
     70 
     71 prod = accumulator( 3.0 );
     72 // returns ~1.817
     73 
     74 prod = accumulator();
     75 // returns ~1.817
     76 ```
     77 
     78 </section>
     79 
     80 <!-- /.usage -->
     81 
     82 <section class="notes">
     83 
     84 ## Notes
     85 
     86 -   Input values are **not** type checked. If provided `NaN` or a value which, when used in computations, results in `NaN`, the accumulated value is `NaN` for **all** future invocations. If non-numeric inputs are possible, you are advised to type check and handle accordingly **before** passing the value to the accumulator function.
     87 
     88 </section>
     89 
     90 <!-- /.notes -->
     91 
     92 <section class="examples">
     93 
     94 ## Examples
     95 
     96 <!-- eslint no-undef: "error" -->
     97 
     98 ```javascript
     99 var randu = require( '@stdlib/random/base/randu' );
    100 var incrgmean = require( '@stdlib/stats/incr/gmean' );
    101 
    102 var accumulator;
    103 var v;
    104 var i;
    105 
    106 // Initialize an accumulator:
    107 accumulator = incrgmean();
    108 
    109 // For each simulated value, update the geometric mean...
    110 for ( i = 0; i < 100; i++ ) {
    111     v = randu() * 100.0;
    112     accumulator( v );
    113 }
    114 console.log( accumulator() );
    115 ```
    116 
    117 </section>
    118 
    119 <!-- /.examples -->
    120 
    121 <section class="links">
    122 
    123 [geometric-mean]: https://en.wikipedia.org/wiki/Geometric_mean
    124 
    125 </section>
    126 
    127 <!-- /.links -->