time-to-botec

Benchmark sampling in different programming languages
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README.md (5118B)


      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 # everyByRight
     22 
     23 > Test whether all elements in a collection pass a test implemented by a predicate function, iterating from right to left.
     24 
     25 <!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->
     26 
     27 <section class="intro">
     28 
     29 </section>
     30 
     31 <!-- /.intro -->
     32 
     33 <!-- Package usage documentation. -->
     34 
     35 <section class="usage">
     36 
     37 ## Usage
     38 
     39 ```javascript
     40 var everyByRight = require( '@stdlib/utils/every-by-right' );
     41 ```
     42 
     43 #### everyByRight( collection, predicate\[, thisArg ] )
     44 
     45 Tests whether all elements in a `collection` pass a test implemented by a `predicate` function, iterating from right to left.
     46 
     47 ```javascript
     48 function isPositive( value ) {
     49     return ( value > 0 );
     50 }
     51 
     52 var arr = [ 1, 2, 3, 4 ];
     53 
     54 var bool = everyByRight( arr, isPositive );
     55 // returns true
     56 ```
     57 
     58 If a `predicate` function returns a non-truthy value, the function **immediately** returns `false`.
     59 
     60 ```javascript
     61 function isPositive( value ) {
     62     return ( value > 0 );
     63 }
     64 
     65 var arr = [ 1, -2, 3, 4 ];
     66 
     67 var bool = everyByRight( arr, isPositive );
     68 // returns false
     69 ```
     70 
     71 The invoked `function` is provided three arguments:
     72 
     73 -   `value`: collection element
     74 -   `index`: collection index
     75 -   `collection`: input collection
     76 
     77 To set the function execution context, provide a `thisArg`.
     78 
     79 ```javascript
     80 function sum( value ) {
     81     if ( value < 0 ) {
     82         return false;
     83     }
     84     this.sum += value;
     85     this.count += 1;
     86     return true;
     87 }
     88 
     89 var arr = [ 1, 2, 3, 4 ];
     90 
     91 var context = {
     92     'sum': 0,
     93     'count': 0
     94 };
     95 
     96 var bool = everyByRight( arr, sum, context );
     97 // returns true
     98 
     99 var mean = context.sum / context.count;
    100 // returns 2.5
    101 ```
    102 
    103 </section>
    104 
    105 <!-- /.usage -->
    106 
    107 <!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
    108 
    109 <section class="notes">
    110 
    111 ## Notes
    112 
    113 -   A `collection` may be either an [`Array`][mdn-array], [`Typed Array`][mdn-typed-array], or an array-like [`Object`][mdn-object] (excluding `strings` and `functions`).
    114 
    115 -   If provided an empty collection, the function returns `true`.
    116 
    117     ```javascript
    118     function untrue() {
    119         return false;
    120     }
    121     var bool = everyByRight( [], untrue );
    122     // returns true
    123     ```
    124 
    125 -   The function differs from [`Array.prototype.every`][mdn-array-every] in the following ways:
    126 
    127     -   The function does **not** skip `undefined` elements.
    128 
    129         <!-- eslint-disable no-sparse-arrays, stdlib/doctest-marker -->
    130 
    131         ```javascript
    132         function log( value, index ) {
    133             console.log( '%s: %s', index, value );
    134             return true;
    135         }
    136 
    137         var arr = [ 1, , , 4 ];
    138 
    139         var bool = everyByRight( arr, log );
    140         /* =>
    141             3: 4
    142             2: undefined
    143             1: undefined
    144             0: 1
    145         */
    146         ```
    147 
    148     -   The function provides limited support for dynamic collections (i.e., collections whose `length` changes during execution). Note, however, that index incrementation is **not** guaranteed to be monotonically **decreasing**.
    149 
    150 </section>
    151 
    152 <!-- /.notes -->
    153 
    154 <!-- Package usage examples. -->
    155 
    156 <section class="examples">
    157 
    158 ## Examples
    159 
    160 <!-- eslint no-undef: "error" -->
    161 
    162 ```javascript
    163 var randu = require( '@stdlib/random/base/randu' );
    164 var everyByRight = require( '@stdlib/utils/every-by-right' );
    165 
    166 function isPositive( value ) {
    167     return ( value > 0 );
    168 }
    169 
    170 var bool;
    171 var arr;
    172 var i;
    173 
    174 arr = new Array( 100 );
    175 for ( i = 0; i < arr.length; i++ ) {
    176     arr[ i ] = randu();
    177 }
    178 
    179 bool = everyByRight( arr, isPositive );
    180 // returns <boolean>
    181 ```
    182 
    183 </section>
    184 
    185 <!-- /.examples -->
    186 
    187 <!-- 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. -->
    188 
    189 <section class="references">
    190 
    191 </section>
    192 
    193 <!-- /.references -->
    194 
    195 <!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
    196 
    197 <section class="links">
    198 
    199 [mdn-array]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array
    200 
    201 [mdn-typed-array]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray
    202 
    203 [mdn-object]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object
    204 
    205 [mdn-array-every]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/every
    206 
    207 </section>
    208 
    209 <!-- /.links -->