time-to-botec

Benchmark sampling in different programming languages
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README.md (3008B)

      1 <!--
      2 
      3 @license Apache-2.0
      4 
      5 Copyright (c) 2020 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 # incrnansum
     22 
     23 > Compute a sum incrementally, ignoring `NaN` values.
     24 
     25 <section class="intro">
     26 
     27 The sum is defined as
     28 
     29 <!-- <equation class="equation" label="eq:sum" align="center" raw="s = \sum_{i=0}^{n-1} x_i" alt="Equation for the sum."> -->
     30 
     31 <div class="equation" align="center" data-raw-text="s = \sum_{i=0}^{n-1} x_i" data-equation="eq:sum">
     32     <img src="https://cdn.jsdelivr.net/gh/stdlib-js/stdlib@eb48b7659e2110aba9fb9c120942cee2e0c4bf5c/lib/node_modules/@stdlib/stats/incr/nansum/docs/img/equation_sum.svg" alt="Equation for the sum.">
     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 incrnansum = require( '@stdlib/stats/incr/nansum' );
     48 ```
     49 
     50 #### incrnansum()
     51 
     52 Returns an accumulator `function` which incrementally computes a sum, ignoring `NaN` values.
     53 
     54 ```javascript
     55 var accumulator = incrnansum();
     56 ```
     57 
     58 #### accumulator( \[x] )
     59 
     60 If provided an input value `x`, the accumulator function returns an updated sum. If not provided an input value `x`, the accumulator function returns the current sum.
     61 
     62 ```javascript
     63 var accumulator = incrnansum();
     64 
     65 var sum = accumulator( 2.0 );
     66 // returns 2.0
     67 
     68 sum = accumulator( 1.0 );
     69 // returns 3.0
     70 
     71 sum = accumulator( NaN );
     72 // returns 3.0
     73 
     74 sum = accumulator( 3.0 );
     75 // returns 6.0
     76 
     77 sum = accumulator();
     78 // returns 6.0
     79 ```
     80 
     81 </section>
     82 
     83 <!-- /.usage -->
     84 
     85 <section class="notes">
     86 
     87 ## Notes
     88 
     89 -   Input values are **not** type checked. If non-numeric inputs are possible, you are advised to type check and handle accordingly **before** passing the value to the accumulator function.
     90 -   For long running accumulations or accumulations of large numbers, care should be taken to prevent overflow.
     91 
     92 </section>
     93 
     94 <!-- /.notes -->
     95 
     96 <section class="examples">
     97 
     98 ## Examples
     99 
    100 <!-- eslint no-undef: "error" -->
    101 
    102 ```javascript
    103 var randu = require( '@stdlib/random/base/randu' );
    104 var incrnansum = require( '@stdlib/stats/incr/nansum' );
    105 
    106 var accumulator;
    107 var v;
    108 var i;
    109 
    110 // Initialize an accumulator:
    111 accumulator = incrnansum();
    112 
    113 // For each simulated datum, update the sum...
    114 for ( i = 0; i < 100; i++ ) {
    115     if ( randu() < 0.2 ) {
    116         v = NaN;
    117     } else {
    118         v = randu() * 100.0;
    119     }
    120     accumulator( v );
    121 }
    122 console.log( accumulator() );
    123 ```
    124 
    125 </section>
    126 
    127 <!-- /.examples -->
    128 
    129 <section class="references">
    130 
    131 </section>
    132 
    133 <!-- /.references -->
    134 
    135 <section class="links">
    136 
    137 </section>
    138 
    139 <!-- /.links -->