color leaves out data

The command

pcolor(1:4, 1:4, randn(4,4))

produces a tiled plot with 9 colors even though

randn(4,4)

is a collection of 16 numbers. What happened to the other 5?

Answer 1

[Image Analyst]

Yes. pcolor() leaves off the last row and column. Don't use it - I never do. Use imshow() instead. Or, if you have an old version of MATLAB, or don't have the Image Processing Toolbox, use image() or imagesc().