Run results for: Testing character counting

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/102.0.5005.61 Safari/537.36

Browser: Chrome 102

Operating system: Windows

Device Platform: Desktop

Date tested: 2 years ago

Test name	Executions per second
Match	16062125.0 Ops/sec
Split	14865070.0 Ops/sec
For loop - access with count	2858150.5 Ops/sec
For loop - searching for a single character	172816.8 Ops/sec
element mapping and filtering with position	2246621.0 Ops/sec
deleting the character out of the string and measuring the distance in length	5605556.0 Ops/sec
based on typed arrays access with cnt	349560.8 Ops/sec
based on untyped Arrays access with cnt	365906.3 Ops/sec
Using reduce	605461.7 Ops/sec
Histogram dict	72845.0 Ops/sec
split filtering with destructor	5634831.0 Ops/sec
Sanity check for loop	604556.2 Ops/sec
Sanity check for loop with of	1738920.4 Ops/sec
For loop indexOf slicing	5107123.5 Ops/sec
For loop indexOf from position	5594127.0 Ops/sec

Script Preparation code:

 var stringsearch = "o", str = "this is foo bar";

str2buffer = function(s){ var bu = new ArrayBuffer(s.length), aUint8 = new Uint8Array(bu );
                         for(var i=0; i<bu.byteLength; aUint8[i]=s.charCodeAt(i),i++);return aUint8;
                        };
var bstr = str2buffer ("this is foo bar")
,schar = 'o'.charCodeAt()
,cnt=0;

var ubstr = "this is foo bar".split('').map( function(e,i){ return e.charCodeAt();} )
       ,schar = 'o'.charCodeAt()
       ,cnt=0;
var hist = {};
var len = str.length;

function countChar (char, search) {
  
  let num = 0;
  let str = search;
  let pos = str.indexOf(char);
  
  while(pos > -1) {
    str = str.slice(pos + 1);
    pos = str.indexOf(char);
    num++;
  }

  return num;

}

function countChar2 (char, str) {
  
  let num = 0;
  let pos = str.indexOf(char);
  
  while(pos > -1) {
    pos = str.indexOf(char, pos + 1);
    num++;
  }

  return num;

}

Tests:

Match
("this is foo bar".match(/o/g)||[]).length;
Split
"this is foo bar".split("o").length-1;
For loop - access with count
for(var count=-1,index=-2; index != -1; count++,index=str.indexOf(stringsearch,index+1));
For loop - searching for a single character
for(var i=count=0; i<str.length; count+=+(stringsearch===str[i++]));
element mapping and filtering with position
str.split('').map( function(e,i){ if(e === 'o') return i;} ).filter(Boolean).length;
deleting the character out of the string and measuring the distance in length
str.length - str.replace(/o/g,'').length;
based on typed arrays access with cnt
for(var i=0;i<bstr.byteLength;schar!==bstr[i++]||cnt++);
based on untyped Arrays access with cnt
for(var i=0;i<ubstr.length;schar!==ubstr[i++]||cnt++);
Using reduce
str.split('').reduce(function(p,c,i,a){ if(c === schar || p === schar){return isNaN(parseInt(p))? 1:+p+1;} return p;})
Histogram dict
for (si in str) { hist[str[si]] = hist[str[si]] ? 1+hist[str[si]]:1; }
split filtering with destructor
[...str].filter(l => l === 'o').length;
Sanity check for loop
for (let charIndex = 0; charIndex < len; ++charIndex) { if (str[charIndex] === ',') { count++; } }
Sanity check for loop with of
for (const char of str) { if (char === 'o') { count++; } }
For loop indexOf slicing
countChar(stringsearch, str);
For loop indexOf from position
countChar2(stringsearch, str);

Run results for: Testing character counting

Match

Split

For loop - access with count

For loop - searching for a single character

element mapping and filtering with position

deleting the character out of the string and measuring the distance in length

based on typed arrays access with cnt

based on untyped Arrays access with cnt

Using reduce

Histogram dict

split filtering with destructor

Sanity check for loop

Sanity check for loop with of

For loop indexOf slicing

For loop indexOf from position