Question

What I would like to do is replace the two if statements with a single mathematical formula. I can’t for the life of me figure out how, as mathematics was never my strong point. Any advice would be greatly appreciated.

<script>

var x, y, z;
x = 200;
y = 100;
i = 0;

 while(z != y) {

    i++;

    if (x < y) z = x + i;
    if (x > y) z = x - i;

    document.write(z + "<br>");

}


</script>

Edit: the real code looks like this. It’s not too pretty, was hoping I could shrink it down to two lines.

if (prevposX < newposX) posX = prevposX + animStep_;
if (prevposX > newposX) posX = prevposX - animStep_;
if (prevposY < newposY) posY = prevposY + animStep_;
if (prevposY > newposY) posY = prevposY - animStep_;

Edit:

It has been a while, but I believe the Modulus (%) operator would have helped me. I’ve now moved on to a library to do graphics for me so I didn’t need it in the end.

Answer 1

You can make use of a ternary operator

z = x + ((x<y) ? i : -i)

This assumes that when x >= y then you want to -i. If you want to stick exactly to your original you need a second ternary operator, which gets a bit messy:

z = x + ((x<y) ? i : ((x>y) ? -i : 0))

Frankly, it might be clearer to just keep it on 2 lines with 2 if statements like you already have.