time-to-botec

Benchmark sampling in different programming languages
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README.md (2921B)

      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 # Fibonacci Number Index
     22 
     23 > Compute the [Fibonacci number][fibonacci-number] index.
     24 
     25 <section class="intro">
     26 
     27 The [Fibonacci number][fibonacci-number] index is given by
     28 
     29 <!-- <equation class="equation" label="eq:fibonacci_number_index" align="center" raw="n = \left \lfloor{\log_\varphi \biggl(F \cdot \sqrt{5} + \tfrac{1}{2}\biggr)}\right \rfloor" alt="Formula to compute the Fibonacci number index."> -->
     30 
     31 <div class="equation" align="center" data-raw-text="n = \left \lfloor{\log_\varphi \biggl(F \cdot \sqrt{5} + \tfrac{1}{2}\biggr)}\right \rfloor" data-equation="eq:fibonacci_number_index">
     32     <img src="https://cdn.jsdelivr.net/gh/stdlib-js/stdlib@bb29798906e119fcb2af99e94b60407a270c9b32/lib/node_modules/@stdlib/math/base/special/fibonacci-index/docs/img/equation_fibonacci_number_index.svg" alt="Formula to compute the Fibonacci number index.">
     33     <br>
     34 </div>
     35 
     36 <!-- </equation> -->
     37 
     38 where `φ` is the [golden ratio][golden-ratio] and `F > 1`.
     39 
     40 </section>
     41 
     42 <!-- /.intro -->
     43 
     44 <section class="usage">
     45 
     46 ## Usage
     47 
     48 ```javascript
     49 var fibonacciIndex = require( '@stdlib/math/base/special/fibonacci-index' );
     50 ```
     51 
     52 #### fibonacciIndex( F )
     53 
     54 Computes the [Fibonacci number][fibonacci-number] index for `F_n > 1`.
     55 
     56 ```javascript
     57 var n = fibonacciIndex( 2 );
     58 // returns 3
     59 
     60 n = fibonacciIndex( 3 );
     61 // returns 4
     62 
     63 n = fibonacciIndex( 5 );
     64 // returns 5
     65 ```
     66 
     67 If provided either a non-integer or `F_n <= 1`, the function returns `NaN`. 
     68 
     69 ```javascript
     70 var n = fibonacciIndex( -1 );
     71 // returns NaN
     72 
     73 n = fibonacciIndex( 3.14 );
     74 // returns NaN
     75 ```
     76 
     77 If provided `NaN`, the function returns `NaN`.
     78 
     79 ```javascript
     80 var n = fibonacciIndex( NaN );
     81 // returns NaN
     82 ```
     83 
     84 </section>
     85 
     86 <!-- /.usage -->
     87 
     88 <section class="notes">
     89 
     90 </section>
     91 
     92 <!-- /.notes -->
     93 
     94 <section class="examples">
     95 
     96 ## Examples
     97 
     98 <!-- eslint no-undef: "error" -->
     99 
    100 ```javascript
    101 var fibonacciIndex = require( '@stdlib/math/base/special/fibonacci-index' );
    102 
    103 var F1;
    104 var F2;
    105 var FN;
    106 var n;
    107 var i;
    108 
    109 F1 = 1;
    110 F2 = 1;
    111 for ( i = 3; i < 79; i++ ) {
    112     FN = F1 + F2;
    113     F1 = F2;
    114     F2 = FN;
    115     n = fibonacciIndex( FN );
    116     console.log( 'n(%d) = %d', FN, n );
    117 }
    118 ```
    119 
    120 </section>
    121 
    122 <!-- /.examples -->
    123 
    124 <section class="links">
    125 
    126 [fibonacci-number]: https://en.wikipedia.org/wiki/Fibonacci_number
    127 
    128 [golden-ratio]: https://en.wikipedia.org/wiki/Golden_ratio
    129 
    130 </section>
    131 
    132 <!-- /.links -->