time-to-botec

Benchmark sampling in different programming languages
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README.md (4134B)

      1 <!--
      2 
      3 @license Apache-2.0
      4 
      5 Copyright (c) 2019 The Stdlib Authors.
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      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 # itermmidrange
     22 
     23 > Create an [iterator][mdn-iterator-protocol] which iteratively computes a moving [mid-range][mid-range].
     24 
     25 <section class="intro">
     26 
     27 The [**mid-range**][mid-range], or **mid-extreme**, is the arithmetic mean of maximum and minimum values. Accordingly, the [mid-range][mid-range] is the midpoint of the [range][range] and a measure of central tendency.
     28 
     29 </section>
     30 
     31 <!-- /.intro -->
     32 
     33 <!-- Package usage documentation. -->
     34 
     35 <section class="usage">
     36 
     37 ## Usage
     38 
     39 ```javascript
     40 var itermmidrange = require( '@stdlib/stats/iter/mmidrange' );
     41 ```
     42 
     43 #### itermmidrange( iterator, W )
     44 
     45 Returns an [iterator][mdn-iterator-protocol] which iteratively computes a moving [mid-range][mid-range]. The `W` parameter defines the number of iterated values over which to compute the moving [mid-range][mid-range].
     46 
     47 ```javascript
     48 var array2iterator = require( '@stdlib/array/to-iterator' );
     49 
     50 var arr = array2iterator( [ 2.0, 1.0, 3.0, -7.0, -5.0 ] );
     51 var it = itermmidrange( arr, 3 );
     52 
     53 // Fill the window...
     54 var v = it.next().value; // [2.0]
     55 // returns 2.0
     56 
     57 v = it.next().value; // [2.0, 1.0]
     58 // returns 1.5
     59 
     60 v = it.next().value; // [2.0, 1.0, 3.0]
     61 // returns 2.0
     62 
     63 // Window begins sliding...
     64 v = it.next().value; // [1.0, 3.0, -7.0]
     65 // returns -2.0
     66 
     67 v = it.next().value; // [3.0, -7.0, -5.0]
     68 // returns -2.0
     69 ```
     70 
     71 </section>
     72 
     73 <!-- /.usage -->
     74 
     75 <!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
     76 
     77 <section class="notes">
     78 
     79 ## Notes
     80 
     81 -   If an iterated value is non-numeric (including `NaN`), the function returns `NaN` for **at least** `W-1` future invocations. If non-numeric iterated values are possible, you are advised to provide an [`iterator`][mdn-iterator-protocol] which type checks and handles non-numeric values accordingly.
     82 -   As `W` values are needed to fill the window buffer, the first `W-1` returned values are calculated from smaller sample sizes. Until the window is full, each returned value is calculated from all previously iterated values.
     83 
     84 </section>
     85 
     86 <!-- /.notes -->
     87 
     88 <!-- Package usage examples. -->
     89 
     90 <section class="examples">
     91 
     92 ## Examples
     93 
     94 <!-- eslint no-undef: "error" -->
     95 
     96 ```javascript
     97 var runif = require( '@stdlib/random/iter/uniform' );
     98 var itermmidrange = require( '@stdlib/stats/iter/mmidrange' );
     99 
    100 // Create an iterator for generating uniformly distributed pseudorandom numbers:
    101 var rand = runif( -10.0, 10.0, {
    102     'seed': 1234,
    103     'iter': 100
    104 });
    105 
    106 // Create an iterator for iteratively computing a moving mid-range:
    107 var it = itermmidrange( rand, 3 );
    108 
    109 // Perform manual iteration...
    110 var v;
    111 while ( true ) {
    112     v = it.next();
    113     if ( typeof v.value === 'number' ) {
    114         console.log( 'mid-range: %d', v.value );
    115     }
    116     if ( v.done ) {
    117         break;
    118     }
    119 }
    120 ```
    121 
    122 </section>
    123 
    124 <!-- /.examples -->
    125 
    126 <!-- Section to include cited references. If references are included, add a horizontal rule *before* the section. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
    127 
    128 <section class="references">
    129 
    130 </section>
    131 
    132 <!-- /.references -->
    133 
    134 <!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
    135 
    136 <section class="links">
    137 
    138 [range]: https://en.wikipedia.org/wiki/Range_%28statistics%29
    139 
    140 [mid-range]: https://en.wikipedia.org/wiki/Mid-range
    141 
    142 [mdn-iterator-protocol]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Iteration_protocols#The_iterator_protocol
    143 
    144 </section>
    145 
    146 <!-- /.links -->