关于js算法行列互换

HTML代码的话就是

<ul id="ul1"></ul>

css

body,ul,li{margin: 0;padding: 0;font-family: "黑体";background: #eee;}
li{list-style: none;}
#ul1{margin: 20px auto;border-top: 1px solid #666;border-left: 1px solid #666;overflow: hidden;text-align: center;}
#ul1 li{float: left;border-bottom: 1px solid #666;border-right: 1px solid #666;font-size: 18px;transition:background 1s linear;}

js

var oUl = document.getElementById('ul1');
    var aLi = oUl.getElementsByTagName('li');
    var size = 10;
    var sizeGrid = 60;
    var len = size*size;
    var arr = [];

    oUl.style.width = size*(sizeGrid + 1) + 'px';
    oUl.style.height = size*(sizeGrid + 1) + 'px';

    for(var i=0; i<len; i++){
        var oLi = document.createElement('li');
        oLi.style.width = sizeGrid + 'px';
        oLi.style.height = sizeGrid + 'px';
        oLi.innerHTML = i;
        oLi.style.lineHeight = sizeGrid + 'px';
        arr.push( i );
        oLi.style.background = "rgba(" +Math.floor(Math.random()*255 + 1)+ "," +Math.floor(Math.random()*255 + 1)+ "," +Math.floor(Math.random()*255 + 1)+ "," +.5+  ")";
        //console.log( arr );
        oUl.appendChild( oLi );
    }
    console.log( aLi.length );

    setInterval(function(){
        for(var i=0; i<aLi.length; i++){
            aLi[i].style.background = "rgba(" +Math.floor(Math.random()*255 + 1)+ "," +Math.floor(Math.random()*255 + 1)+ "," +Math.floor(Math.random()*255 + 1)+ "," +.5+  ")";
        }
        console.log(1);
    }, 1500);

    arr = changeXY(arr);
    //console.log( arr );
    for(var i=0; i<arr.length; i++){
        aLi[i].innerHTML = arr[i];
    }

    function changeXY( arr ){
        var newArr = [];
        var iNow = 0;
        (function(){
            if(size == iNow){
                return;
            }
            for(var i=0; i<arr.length; i++){
                if( i%size == iNow){
                    newArr.push( arr[i] );
                }
            }
            iNow++;
            arguments.callee();
        })()
        /*for(var i=0; i<arr.length; i++){
            if( i%size == iNow){
                newArr.push( arr[i] );
            }
        }*/
        //console.log( newArr );
        return newArr;
    }