class_docstr: This is a mixin class to support scalar data to RGBA mapping.
  The ScalarMappable makes use of data normalization before returning
  RGBA colors from the given colormap.
docstr: set the colormap for luminance data
  
  ACCEPTS: a colormap or registered colormap name
docstr_tok: ["set","the","colormap","for","luminance","data","ACCEPTS",":","a","colormap","or","registered","colormap","name"]
code: def set_cmap(self, cmap):
      """
      set the colormap for luminance data
  
      ACCEPTS: a colormap or registered colormap name
      """
      cmap = get_cmap(cmap)
      self.cmap = cmap
      self.changed()
  
imports: from __future__ import absolute_import, division, print_function, unicode_literals
  import six
  import numpy
  from numpy import ma
  import matplotlib
  import matplotlib.colors
  import matplotlib.cbook
  from matplotlib._cm import datad
  from matplotlib._cm_listed import cmaps
label_desc: Use image node_id 8 for calling the ScalarMappable obj's underlying member method code with example usage: obj.set_cmap(cmap) without return types