animating an element's height using jquery

Question

I have some bars that are filled with a height %, but right when the page loads I would like all the bars to fill up and then decrease to 0. I know how to fill it up with a for

Answer 1

You can do it all in one loop:

for(var i = 0; i <= 200; i++) {
    var height = (i <=100) ? i : 200 - i;
}

The variable height will go from 0 to 100 and then back to 0.