Change colour on grid

Hi,

How would I change the colour of the little square island in my waves simulation?

Answer 1

[Mathieu NOE]

hello Andrew

one solution is to overlay two mesh plots and ask for the second to have a single bright color (here red)

either only the mesh is red but you can also have plain (face) color as shown in the second example :

[X,Y] = meshgrid(-15:.5:15);
R = sqrt(X.^2 + Y.^2) + eps;
Z = sin(R).*R;
[m,n] = size(Z);
% create inner flat square
ind = round(m/2) + (-10:10);
Z(ind,ind) = 0;

figure
mesh(X,Y,Z)
hold on 
m = mesh(X(ind,ind),Y(ind,ind),Z(ind,ind));
set(m,'Edgecolor','r');
% set(m,'Facecolor','r');
view(-30,75)
hold off 

●

figure
mesh(X,Y,Z)
hold on 
m = mesh(X(ind,ind),Y(ind,ind),Z(ind,ind));
set(m,'Edgecolor','r');
set(m,'Facecolor','r');
view(-30,75)
hold off 

[Andrew]

That is great thank you

[Mathieu NOE]

as always, my pleasure

Answer 2

[Constantino Carlos Reyes-Aldasoro]

The colour is going to be related to the values of whatever you are plotting, e.g.,

L = 160*membrane(1,100);
mesh(L)
colorbar

The blue is due to the values in the square region, and it is related to the colormap that you use. You may play with the colormaps to change those values but you will be affecting all the values.

figure
mesh(L)
colorbar
colormap jet

Hope this helps.

[Andrew]

Thanks