Logarithmic colorscale ? Contourf, large range of value
1 view (last 30 days)
Show older comments
Hello,
I'm currently trying to plot Data using contourf(X,Y,Z), where Z values are ranging from 0.01 to -1.6. I'm using the jet colorbar. However, what is interesting to see is between 0 and 0.01, so I would like to have a detailed colorbar between 0 and 0.01, and a small variation between 0 and -1.6. Basically, I would like that the positive values scale in red and the negatives one in blue.
I thought using a logarithmic scaling would help, but it's currently expending the blue and reducing the red, and not giving at all what I want. I used :
cmap = jet
redMap = cmap(:,1);
greenMap = cmap(:,2);
blueMap = cmap(:, 3);
newX = logspace(0, log10(64), 64);
logRedMap = interp1(1:64, redMap, newX);
logGreenMap = interp1(1:64, greenMap, newX);
logBlueMap = interp1(1:64, blueMap, newX);
logMap = [logRedMap; logGreenMap; logBlueMap]';
colormap(logMap);
Note that everything would be super easy if I only had positive values, so I could take the log of my data and it would be ok.
Thanks for the advices.
This is with the natural colormap/colorscale.
And this is when i set everything negative value to zero, so i can see what is interesting. But this solution isn't very satisfying.
This one is after the code I wrote before :
0 Comments
Accepted Answer
Harsh
on 11 May 2017
Hello Cyril,
If you still need help with this, please contact MathWorks Technical Support here: https://www.mathworks.com/support/contact_us/
Please be sure to provide a detailed description of the issue and attach any relevant files / code / examples required to investigate the issue.
0 Comments
More Answers (1)
See Also
Categories
Find more on Blue in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!