+------------------------------------------------ Keith Hughitt ---------+ > Hi all, > > Does anyone know of a good way to create a new LinearSegmentedColormap > based off an existing one? > > I have a function which attempts to generate N "optimal" color map > indices for a given data array. In cases where the number of values > specified in _segmentdata is the same as N, then I can simply > copy _segmentdata and modify the indices and create a new color map. In > many cases, however, the segment data has far fewer interpolation > points, e.g.: > > In [52]: cm.gray._segmentdata > Out[52]: > {'blue': ((0.0, 0, 0), (1.0, 1, 1)), > 'green': ((0.0, 0, 0), (1.0, 1, 1)), > 'red': ((0.0, 0, 0), (1.0, 1, 1))} > > > Other colormaps may have an arbitrary number of interpolation points. > Ideally, what I would like is a way to expand this into N points (e.g. > 256) so that I use that as input for my new map. >
i cannot really help you with your approach, but i also think it's not so elegant to expand cmaps. did you try to understand the way cmaps can be defined by gradient borders? -> http://www.scipy.org/Cookbook/Matplotlib/Show_colormaps i.e. a friend gave me a colormap defined by points and i converted it to something like that (by just looking at the colors): ie_data = { 'red': ((0.00, 0.357, 0.357), (0.50, 1.000, 1.000), (0.75, 1.000, 1.000), (1.00, 1.000, 1.000)), 'green':((0.00, 0.467, 0.467), (0.50, 1.000, 1.000), (0.75, 0.750, 0.750), (1.00, 0.371, 0.371)), 'blue':((0.00, 0.800, 0.800), (0.50, 1.000, 1.000), (0.75, 0.157, 0.157), (1.00, 0.157, 0.157)) } ie = matplotlib.colors.LinearSegmentedColormap('ieMap', ie_data, 256) use it with cmap=ie regards ------------------------------------------------------------------------------ All the data continuously generated in your IT infrastructure contains a definitive record of customers, application performance, security threats, fraudulent activity and more. Splunk takes this data and makes sense of it. Business sense. IT sense. Common sense. http://p.sf.net/sfu/splunk-d2d-oct _______________________________________________ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users