math error

[benonc]

try run this basic math function after a while it starts adding a small fraction to the calculation and it goes nuts, has anyone else encountered this?



_root.totalMoved = new Number(0)
_root.totalMovedActual = new Number(0)
function start(){
_root.totalMovedActual = 0.4
_root.totalMoved +=_root.totalMovedActual;
trace("total Moved "+(50-_root.totalMovedActual));
trace("total Moved Temp2 "+(50-_root.totalMoved))
}

setInterval(start,100)

[jonmack]

It's to do with the fact that numbers stored on any computer will have a limit to their precision. Eventually small descrepencies will add up. It should be fine with integers, up to a limit ( can't remember what it is in flash ) but with floating point numbers you are going to get these "rounding errors" when doing arithmetic on stuff. There's not a lot you can do ( as far as i know ). If you only want it to show 1 decimal place, then you could round the number to 1dp each time.