2 color scheme on contour plot

I am wanting to contour an xy plane with z values. The particular data that I am analyzing is conduction velocity. I have been able to set up the contour plot the way I am wanting but am having trouble with modifying the colors that it is displaying. I am wanting to color the map in Green for areas that have a CV above a particular value and Red in areas when the CV falls below that value.

Answer 1

[Star Strider]

See if this does what you want:

[X,Y] = meshgrid(-10:10);
Z = X.^2 + 0.1*Y.^3;                                    % Create Data

figure(1)
contourf(X, Y, Z, [min(Z(:)); 10])                      % Use The ‘10’ Contour As The Cutoff
colormap([1,0,0; 0,1,0])                                % Define Colours In ‘colormap’

figure(2)
surf(X, Y, Z)
grid on
colormap([1,0,0; 0,1,0])

The surf plot is there simply to demonstrate that the contourf call does what you want. The surf plot does not use a specific cutoff. See the documentation for contourf for a full description of how this particular call to it works.

[Thomas Shannon]

Hey thanks! This is great. Do you mind explaining how you are crating the data/why?

[Star Strider]

My pleasure!

Since I don’t have your data to work with, I create (not ‘crate’ — I didn’t see the typo) data to test the code to be certain it works. If possible, I always test the code I post. If for whatever reason I can’t, I clearly label it as untested code.

The ‘Q1’ assignment (now eliminated in the edited version, and the comment corrected) was a test line that I did not intend to include in the posted code.

[Osvaldo]

Amazing!

[Star Strider]

Osvaldo — I very much appreciate your compliment!