Freely adjust color table
MarkusG
Fri, 03/02/2012 - 03:53 am
Is there a way to adjust the color table a bit more to my own will. As an example, I would like to use the RedWhiteBlue color table inverse. No problem there, of course. Now I would like to have the 0 of my data at white. I can get that done but only if the range for red and blue are equal. But say I would like to have the negative range for blue only run to -0.05 and the the positive for red to 0.1. But still have white to be zero and not 0.025.
Thanks,
Markus
You can basically generate an arbitrary color scale in Igor by mixing the colors you want from RGB. For your example I have generated a color index table (attached). To get this, I extracted the RedWhiteBlue table via
Colortab2Wave RedWhiteBlue, reversed it and filled a wave asymmetrically with the values. The generated color table is a scaled wave from -0.1 to 0.1, but I made it this way, that the vaules from -0.1 to ~-0.05 are all blue. When you use this wave, you go from blue to white between -0.05 and zero and then to red at 0.1. You can adjust the range by rescaling the wave or try to generate your own.March 2, 2012 at 04:53 am - Permalink
I had found the command to extract the wave for a certain color map and already thought that it might be the right way to achieve what I want.
I tried the colorwave that you supplied and thought I understood the motivation behind it.
I think I can adjust it manually now, so thank you for your help.
However, is it just me or is this a rather complicated way of doing it. I would have hoped for way of achieving this a bit more dynamically. Lets say you figure out the minimal and maximal values of your data, chose the color table and then somehow with the mouse pointer can grab one of the colors (white, in my case) and shift it around to give the other colors more or less weight.
Cheers,
Markus
March 2, 2012 at 05:58 am - Permalink