time-to-botec

Benchmark sampling in different programming languages
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README.md (2390B)

      1 <!--
      2 
      3 @license Apache-2.0
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      5 Copyright (c) 2018 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
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     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
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     19 -->
     20 
     21 # Exponent Mask
     22 
     23 > High word mask for the exponent of a [double-precision floating-point number][ieee754].
     24 
     25 <section class="usage">
     26 
     27 ## Usage
     28 
     29 <!-- eslint-disable id-length -->
     30 
     31 ```javascript
     32 var FLOAT64_HIGH_WORD_EXPONENT_MASK = require( '@stdlib/constants/float64/high-word-exponent-mask' );
     33 ```
     34 
     35 #### FLOAT64_HIGH_WORD_EXPONENT_MASK
     36 
     37 High word mask for the exponent of a [double-precision floating-point number][ieee754]. 
     38 
     39 <!-- eslint-disable id-length -->
     40 
     41 ```javascript
     42 // 0x7ff00000 = 2146435072 => 0 11111111111 00000000000000000000
     43 var bool = ( FLOAT64_HIGH_WORD_EXPONENT_MASK === 0x7ff00000 );
     44 // returns true
     45 ```
     46 
     47 </section>
     48 
     49 <!-- /.usage -->
     50 
     51 <section class="notes">
     52 
     53 ## Notes
     54 
     55 -   The higher order word of a [double-precision floating-point number][ieee754] is a 32-bit integer containing the more significant bits which include the exponent and sign.
     56 
     57 </section>
     58 
     59 <!-- /.notes -->
     60 
     61 <section class="examples">
     62 
     63 ## Examples
     64 
     65 <!-- eslint-disable id-length -->
     66 
     67 <!-- eslint no-undef: "error" -->
     68 
     69 ```javascript
     70 var getHighWord = require( '@stdlib/number/float64/base/get-high-word' );
     71 var FLOAT64_HIGH_WORD_EXPONENT_MASK = require( '@stdlib/constants/float64/high-word-exponent-mask' );
     72 
     73 var out;
     74 var hi;
     75 var x;
     76 
     77 x = 11.5;
     78 hi = getHighWord( x ); // => 0 10000000010 01110000000000000000
     79 // returns 1076297728
     80 
     81 // Mask off all bits except for the exponent bits:
     82 out = hi & FLOAT64_HIGH_WORD_EXPONENT_MASK; // => 0 10000000010 00000000000000000000
     83 // returns 1075838976
     84 
     85 // Mask on the exponent bits and leave other bits unchanged:
     86 out = hi | FLOAT64_HIGH_WORD_EXPONENT_MASK; // => 0 11111111111 01110000000000000000
     87 // returns 2146893824
     88 ```
     89 
     90 </section>
     91 
     92 <!-- /.examples -->
     93 
     94 <section class="links">
     95 
     96 [ieee754]: http://en.wikipedia.org/wiki/IEEE_754-1985
     97 
     98 </section>
     99 
    100 <!-- /.links -->