The value of the switch determines how to display the complex numbers. Currently 2 colormaps are available. If none of the color switches is given, a geographical color mapping is used. If the optional argument number is omitted, the colormap is reset to the default. The numbers select one of the predefined formulae which are used to map the z value to a color intensity.
Negative numbers invert the color intensity.
The average and sigma of the nearest neighbours of each pixel are calculated. The default for scale is 1. The best way to understand this is to compare the results for different scale values. If both min and max are given, a - can be used as separator instead of the , . Integer scaling or binning.