Hi,
After hours of reading, I still couldn’t get the answer.
Please look at the plots below. The top one is a 2-D histogram. It is to indicate the energies of 40 EMC towers in a module, 20 in x, 2 in y. The height of Z indicates the energies. However, because of the physical dimension of each of these towers(delta_x=delta_y), I want the Y axis to be shorter so that the 2-D histogram really looks like a module of 40 towers, except in 3rd dimension. What is the function? Thanks!

I think you can not shorten axis on lego plots. ROOT always wants to draw a cube.

But you can change Y-axis range to be 10 times larger ( and number of bins also 10 time larger). Then your filled bins will have correct shape relative to X-axis. Most of the histogram will be empty of course. May be somebody else knows of another method.

If the number of ploted bins along x and y axis are differents, you get this kind of effect. To get square towers you should have the same number of ploted bins along x and y axis