unique in array (v6)

Revision 6 of this benchmark created by Arif Zaman on

Description

I have changed the size of the arrays to much larger, since that is what will show efficiency in the case where it is needed. Efficiency on tiny arrays doesn't much matter, unless you are doing many arrays.

It appears that much of the code was incorrect. I have fixed it, but not verified to see if the results are identical.

Preparation HTML

<script src="http://documentcloud.github.com/underscore/underscore-min.js"></script>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script>

Setup

var size=1000;
    var arr = Array.apply(0,Array(size)).map(function(i,j){return Math.floor(Math.random()*size)});
    
    var arrclone1 = [], arrclone2 = [], arrclone3 = [];
    for (var i=0; i<size; i++)
        arrclone1[i] = arrclone2[i] = arrclone3[i] = arr[i];
    
    var jqFilter = function(v, k){
        return $.inArray(v ,arr) === k;
    }
    
    Array.prototype.unique = function() {
        var a = [];
        for (var i=0, l=this.length; i<l; i++)
            if (a.indexOf(this[i]) === -1)
                a.push(this[i]);
        return a;
    }
    
    Array.prototype.getUnique = function(){
       var u = {}, a = [];
       for(var i = 0, l = this.length; i < l; ++i){
          if(u.hasOwnProperty(this[i])) continue;
          a.push(this[i]);
          u[this[i]] = 1;
       }
       return a;
    }
    
    Array.prototype.getUnique2 = function(){
       var u = Object.create(null), a = [];
       for(var i = 0, l = this.length; i < l; ++i){
          if(u[this[i]]) continue;
          a.push(this[i]);
          u[this[i]] = 1;
       }
       return a;
    }
    
    Array.prototype.getUnique3 = function(){
       var u = Object.create(null), a = [];
       for(var i = 0, l = this.length; i < l; ++i){
          if(this[i] in u) continue;
          a.push(this[i]);
          u[this[i]] = 1;
       }
       return a;
    }
    
    function onlyUnique(value, index, self) { 
        return self.indexOf(value) === index;
    }
    
    Array.prototype.sortFilter = function() {
        var sorted_arr = this.sort();
        var results = [];
        for (var i = 0; i < this.length - 1; i++) {
            if (sorted_arr[i + 1] != sorted_arr[i]) {
                results.push(sorted_arr[i]);
            }
        }
        if (sorted_arr[this.length - 1] != sorted_arr[this.length - 2]) {
            results.push(sorted_arr[this.leght - 1]);
        }
        return results;
    }
    
    Array.prototype.sortUnique = function() {
        this.sort();
        var last_i;
        for (var i=0; i<this.length; i++)
            if ((last_i = this.lastIndexOf(this[i])) !== i)
                this.splice(i+1, last_i-i);
        return this;
    }

Test runner

Ready to run.

Testing in
TestOps/sec
jQuery grep
$.grep(arr, jqFilter);
ready
Underscore uniq
_.uniq(arr)
ready
My arr.unique
arr.unique();
ready
Rafael's arr.getUnique
arr.getUnique();
ready
TLindig's filter
arrclone1.filter(onlyUnique);
ready
swilliams' sorted testing
arrclone2.sortFilter();
ready
My version of sorted testing
arrclone3.sortUnique();
ready
Sorting my arr.unique
arr.unique().sort();
ready
arr.getUnique2
arr.getUnique2();
ready
arr.getUnique3
arr.getUnique3();
ready

Revisions

You can edit these tests or add more tests to this page by appending /edit to the URL.