#javascript - Fisher-Yates shuffle

gistfile1

jQuery.fn.shuffleChildren = (function(){
    
    function fisherYatesShuffle(arr) {
        
        // Fisher-Yates shuffle has been proven
        // to be more random than the conventional
        // arr.sort(function(){return Math.random()-.5})
        // http://www.robweir.com/blog/2010/02/microsoft-random-browser-ballot.html
        
        var i = arr.length,
            r, tempI, tempR;
        
        if ( i === 0 ) {
            return arr;
        }
        
        while ( i-- ) {
            
            // Generate random index:
            r = Math.floor(Math.random() * (i + 1));
            
            // Shuffle:
            tempI = arr[i];
            tempR = arr[r];
            arr[i] = tempR;
            arr[r] = tempI;
            
        }
        
        return arr;
        
    }
    
    return function(doQuick) {
        
        return this.each(function(){
            
            var container = jQuery(this),
                parentNode = this.parentNode,
                nextSibling = this.nextSibling;
            
            if (doQuick) {
                // Remove from document
                container.detach();
            }
            
            // Append shuffled children
            container.append(
                fisherYatesShuffle(container.children())
            );
            
            if (doQuick) {
                // Insert at the correct location in the document
                parentNode.insertBefore(container[0], nextSibling);
            }
            
        });
        
    };
 
})();