I have two matrices of the same size. The first one is function of two variables, which is to be displayed using pcolor. But then I need to mask (paint with black) part of this plot using the mask defined by the second matrix (zeros for transparent cells, ones for those to be masked). I need the colorbar and caxis to remain from the main pcolor of the function. How can I do this? I suspect this is something to do with AlphaData property of the second graph, but so far I only see the solutions for imshow, but not for pcolor.