How to avoid white patch in contourf ?
16 views (last 30 days)
Show older comments
I am facing a problem from quite a long time. My data range is beyond my colorbar limit. That is why when the minimum value exceeded the colorbar limit it is coming white but it is okay for maximum value. How to solve this? In python something like extend = both works but what about MATLAB?
PS: I don't want to extend my colorbar limit.
8 Comments
Image Analyst
on 23 Mar 2018
You say "when the minimum value exceeded the colorbar limit it is coming white" however, the minimum value (according to the colors) seems to be -1.9. However not all values that exceed your minimum value are white. I see values showing up as red and blue also. In fact, it seems like the only values showing up as white are around the range -0.1 to +0.1.
Anyway, let's assume you want that range to be some color other than white. You can just set the middle of the colormap to that color. What color do you want it to be?
Answers (1)
Kelly Kearney
on 23 Mar 2018
Matlab's contourf function doesn't actually plot contour faces for lower-than-lowest-clevel regions when are unenclosed. (And for that matter, what it does with enclosed lower-than-lowest-clevel regions varies between Matlab versions).
I think my contourfcmap function with the calccontour option should be able to create the plot the way you'd like it.
Alternatively, you can set your axis color to match the lowest value in your colormap... that way empty contour regions will appear the correct color.
4 Comments
Kelly Kearney
on 26 Mar 2018
I'm working on a fix to the NaN issue... may take a day or two. The colorbar enhancement is one that's been on my to-do list for a while... I'll see if I have time for that one as well, but no promises.
You can specify the line style by saving the handles structure (first output of contourfcmap) and then applying any changes you'd like.
Not sure about the data cursor thing... I don't use that myself. If it relies on interacting with a contourgroup object, then that's not really something I can offer, since my function uses simple patches and lines.
See Also
Categories
Find more on Colormaps 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!