How to set the plot box to particular size

How to set the plot box to pixel size.

x = linspace(1,20,100);  
y  = x.^2;   
figure(1)
plot(x,y)
xlabel('X')
ylabel('Y')

The code below will set the figure size. Instead I would like only the plot box without labels to have the size of 200x500.

x0=10;
y0=10;
width = 500;    
height = 200;    
set(gcf,'position',[x0,y0,width,height])