time-to-botec

Benchmark sampling in different programming languages
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README.md (3176B)

      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 # Kernel Cosine
     22 
     23 > Compute the [cosine][cosine] of a number on `[-π/4, π/4]`.
     24 
     25 <section class="usage">
     26 
     27 ## Usage
     28 
     29 ```javascript
     30 var kernelCos = require( '@stdlib/math/base/special/kernel-cos' );
     31 ```
     32 
     33 #### kernelCos( x, y )
     34 
     35 Computes the [cosine][cosine] of a `number` on `[-π/4, π/4]`. For increased accuracy, the number for which the [cosine][cosine] should be evaluated can be supplied as a [double-double number][double-double-arithmetic] (i.e., a non-evaluated sum of two [double-precision floating-point numbers][ieee754] `x` and `y`).
     36 
     37 ```javascript
     38 var v = kernelCos( 0.0, 0.0 );
     39 // returns ~1.0
     40 
     41 v = kernelCos( 3.141592653589793/6.0, 0.0 );
     42 // returns ~0.866
     43 
     44 v = kernelCos( 0.785, -1.144e-17 );
     45 // returns ~0.707
     46 
     47 v = kernelCos( NaN, 0.0 );
     48 // returns NaN
     49 ```
     50 
     51 </section>
     52 
     53 <!-- /.usage -->
     54 
     55 <section class="notes">
     56 
     57 ## Notes
     58 
     59 -   As components of a [double-double number][double-double-arithmetic], the two [double-precision floating-point numbers][ieee754] `x` and `y` must satisfy 
     60 
     61     <!-- <equation class="equation" label="eq:double_double_inequality" align="center" raw="|y| \leq \frac{1}{2} \operatorname{ulp}(x)" alt="Inequality for the two components of a double-double number."> -->
     62 
     63     <div class="equation" align="center" data-raw-text="|y| \leq \frac{1}{2} \operatorname{ulp}(x)" data-equation="eq:double_double_inequality">
     64         <img src="https://cdn.jsdelivr.net/gh/stdlib-js/stdlib@bb29798906e119fcb2af99e94b60407a270c9b32/lib/node_modules/@stdlib/math/base/special/kernel-cos/docs/img/equation_double_double_inequality.svg" alt="Inequality for the two components of a double-double number.">
     65         <br>
     66     </div>
     67 
     68     <!-- </equation> -->
     69 
     70     where `ulp` stands for [units in the last place][ulp].
     71 
     72 </section>
     73 
     74 <!-- /.notes -->
     75 
     76 <section class="examples">
     77 
     78 ## Examples
     79 
     80 <!-- eslint no-undef: "error" -->
     81 
     82 ```javascript
     83 var linspace = require( '@stdlib/array/linspace' );
     84 var PI = require( '@stdlib/constants/float64/pi' );
     85 var kernelCos = require( '@stdlib/math/base/special/kernel-cos' );
     86 
     87 var x = linspace( -PI/4.0, PI/4.0, 100 );
     88 var i;
     89 
     90 for ( i = 0; i < x.length; i++ ) {
     91     console.log( 'kernelCos(%d) = %d', x[ i ], kernelCos( x[ i ], 0.0 ) );
     92 }
     93 ```
     94 
     95 </section>
     96 
     97 <!-- /.examples -->
     98 
     99 <section class="links">
    100 
    101 [cosine]: https://en.wikipedia.org/wiki/Cosine
    102 
    103 [double-double-arithmetic]: https://en.wikipedia.org/wiki/Quadruple-precision_floating-point_format#Double-double_arithmetic
    104 
    105 [ieee754]: https://en.wikipedia.org/wiki/IEEE_floating_point
    106 
    107 [ulp]: https://en.wikipedia.org/wiki/Unit_in_the_last_place
    108 
    109 </section>
    110 
    111 <!-- /.links -->