time-to-botec

Benchmark sampling in different programming languages
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README.md (2339B)

      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 # roundb
     22 
     23 > Round a numeric value to the nearest multiple of b^n on a linear scale.
     24 
     25 <section class="usage">
     26 
     27 ## Usage
     28 
     29 ```javascript
     30 var roundb = require( '@stdlib/math/base/special/roundb' );
     31 ```
     32 
     33 #### roundb( x, n, b )
     34 
     35 Rounds a `numeric` value to the nearest multiple of `b^n` on a linear scale.
     36 
     37 ```javascript
     38 // Round a value to 2 decimal places:
     39 var v = roundb( 3.141592653589793, -2, 10 );
     40 // returns 3.14
     41 
     42 // If n = 0 or b = 1, `roundb` behaves like `round`:
     43 v = roundb( 3.141592653589793, 0, 2 );
     44 // returns 3.0
     45 
     46 // Round a value to the nearest multiple of two:
     47 v = roundb( 5.0, 1, 2 );
     48 // returns 6.0
     49 ```
     50 
     51 </section>
     52 
     53 <!-- /.usage -->
     54 
     55 <section class="notes">
     56 
     57 ## Notes
     58 
     59 -   Due to rounding error in [floating-point numbers][ieee754], rounding may **not** be exact. For example,
     60 
     61     ```javascript
     62     var x = 0.2 + 0.1;
     63     // returns 0.30000000000000004
     64 
     65     // Should round to 0.3...
     66     var v = roundb( x, -16, 10 );
     67     // returns 0.3000000000000001
     68     ```
     69 
     70 </section>
     71 
     72 <!-- /.notes -->
     73 
     74 <section class="examples">
     75 
     76 ## Examples
     77 
     78 <!-- eslint no-undef: "error" -->
     79 
     80 ```javascript
     81 var randu = require( '@stdlib/random/base/randu' );
     82 var round = require( '@stdlib/math/base/special/round' );
     83 var pow = require( '@stdlib/math/base/special/pow' );
     84 var roundb = require( '@stdlib/math/base/special/roundb' );
     85 
     86 var x;
     87 var n;
     88 var b;
     89 var v;
     90 var i;
     91 
     92 for ( i = 0; i < 100; i++ ) {
     93     x = (randu()*100.0) - 50.0;
     94     n = round( (randu()*10.0) - 5.0 );
     95     b = round( randu()*10.0 );
     96     v = roundb( x, n, b );
     97     console.log( 'x: %d. %d^%d: %d. Rounded: %d.', x, b, n, pow( b, n ), v );
     98 }
     99 ```
    100 
    101 </section>
    102 
    103 <!-- /.examples -->
    104 
    105 <section class="links">
    106 
    107 [ieee754]: https://en.wikipedia.org/wiki/IEEE_754-1985
    108 
    109 </section>
    110 
    111 <!-- /.links -->