How to use different colormaps for different function in mesh plot.

Using different colormaps for same axis is not logical but if I want want to somehow do it then what should I do?

x = linspace(-3,3,100); y = linspace(0,3,100);
[X,Y] = meshgrid(x,y);
Rho2 = X.*X + Y.*Y;
Z = exp(-Rho2);
Z1 = sin(sqrt(Rho2));

figure,
mesh(X,Y,Z,'FaceAlpha',1);  hold on 
mesh(X,Y,Z1,'FaceAlpha',1); 

I'm using R2021a and freezColors function is not suporting, it shows error. Perhaps I'm using it wrong. Anybody has any idea how to do it?

Appriciate your help.

[Walter Roberson]

freezeColors() is a File Exchange contribution; https://www.mathworks.com/matlabcentral/fileexchange/7943-freezecolors-unfreezecolors

You need to install it to use it (possibly use the Add-On Explorer to install it)

Answer 1

[Voss]

Here is one way:

% data
x = linspace(-3,3,100); y = linspace(0,3,100);
[X,Y] = meshgrid(x,y);
Rho2 = X.*X + Y.*Y;
Z = exp(-Rho2);
Z1 = sin(sqrt(Rho2));

% pick some colormaps
cmap = parula();
cmap1 = turbo();

% convert Z and Z1 into colors based on their respective colormaps
C = ind2rgb(round(rescale(Z,1,size(cmap,1))),cmap);
C1 = ind2rgb(round(rescale(Z1,1,size(cmap1,1))),cmap1);

% plot the meshes
figure
mesh(X,Y,Z,C,'FaceAlpha',1);  hold on 
mesh(X,Y,Z1,C1,'FaceAlpha',1);

[U B]

Didn't know this method. Thank you so much.

[Voss]

You're welcome!

[U B]

Sorry to disturb you again but can I use the same method in contour plot also?

lets say for -

contourf(X,Y,Z,70,'edgecolor','none') ; hold on
contourf(X,Y,Z1,70,'edgecolor','none'); hold off  

[Voss]

No, I don't think so.

The options listed here for countour plots

https://www.mathworks.com/help/matlab/ref/matlab.graphics.chart.primitive.contour-properties.html

basically boil down to 1) a constant color everywhere, or 2) using the current colormap. Since an axes can have only one colormap, you'd have to use the same colormap for all contour plots in a given axes. There doesn't appear to be a way to specify an array of RGB colors for a contour like you can for a surface/mesh.