an indexed CcmbColor table
A ColorTable has a set of Ncol colors which can be indexed individually or mapped onto real values. In the latter case, they are spread uniformly between Cmin and Cmax with values beyond this range being colorless or set to the extreme values according to the fillAbove and fillBelow fields.
The CcmbColor table does its best not to lose information as you change its size: each time you set a CcmbColor manually, the present size of the table becomes the true resolution.