Scroll an image with jQuery

[Jacobb123]

I am trying to scroll an image with jquery from one point to another with jQuery

I am using the following code but cannot seem to get it to work

PHP Code:

var pos = $window.scrollTop(); //position of the scrollbar
var windowHeight = $window.height(); //get the height of the window

function test(startPos, endPos, scrollPos, windowHeight)
    {
        
        var obj = $('#ios');
        var position = obj.position();
        console.log(position.top +  (startPos - endPos)/ (scrollPos/100))
        return (position.top +  (startPos - endPos)/ (scrollPos/100))
    
    }

$ios.css({'top':test(500, 120, pos, windowHeight) }); 


Nothing moves though. Can anyone give me a hint. TO be honest I am so turned around I don't know if I am anywhere close anymore