Plot figure size and aspect ratio

Question

Hi, all,

Is there any way to tell sho to preserve the aspect ratio, when drawing plot()? By default, it renders the figure window in the usual 4:3 or so width:heigh ratio. But say I have a square plot 

plot([0.0,1.0],[0.0,1.0])

and would like the X and Y axes be of the same length (in terms of pixels on the screen). Any ideas?

Thanks,
Jurgis