my if condition is not working on processing language

im working on processing language for my assignment. its an animation. the animation object(a ball) needs to go from up to bottom. i have declared a variable {float x,y} whenever i put if condition to increase it by 1 but its not moving a single inch.

this is for mac 2011

float x;
float y;

size(600, 400)

x = 0.4*width/8;
y = 0.4*height/8;


ellipse( width/2, x, 0.8*width/8, 0.8*width/8);
ellipse( y, height/2, 0.8*height/8, 0.8*height/8);



if(x<height){
x=x+1;
}

if(y<width){
y=y+1;
}

i expect the output is- the ball located on top gows down and stop at the bottom and the left ball goes to right and stop at the rightmost point.