Create a monochrome-compatible colour map
cmap = CMRmap
cmap = CMRmap(M)
cmap = CMRmap returns a colour map CMAP (varying black - purple - red - yellow - white) that is monochrome-compatible, i.e. it produces a monotonic greyscale colour map. CMAP is size Mx3, where M is the length of the current figure's colormap. If no figure exists, MATLAB creates one.
cmap = CMRmap(M) sets the colormap length to M.
The map is a slight modification to that suggested in .
 Rappaport, C. 2002: "A Color Map for Effective Black-and-White Rendering of Color Scale Images", IEEE Antenna's and Propagation Magazine, Vol.44, No.3, pp.94-96 (June).