Hey, in pcolor the X and Y means predefined grid (like frommeshgrid ), and Z are actual data. So then X Y and Z has to be matrixes. If you have 1D X and Y and 2D Z then you can use meshgrid to generate 2D X and Y and usepcolor . If you had 1D Z, or all of your X Y Z are actual depth data, then you will have to display them as 1D data, or expand them to actual 2D array, create grid for them and usepcolor to display them. (And display colorbar as u did write in your answer.) Also check examples forpcolor they might help you to understad how this function works.