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Matlab surf with various color schemes

I have a map of the area on which I would like to present some data. See image below:

enter image description here

The area on the right, surrounded by white, represents a separate surfing function for the rest of the chart. What I would like to do is change the color scheme. Appearance should be gray, and inside should be one color based on the value that I share on the graph. Currently I tried the colormap function (gray), then changed, but that changed the whole graph.

I am open to suggestions about different building styles, i.e. plot3 instead of surfing. So the data I have to do for these two surfs is two lists of points x, y, z.

If possible, I would also like to display a color bar representing the color of the circled area (which I will set based on the external value).

Does anyone know a good way to do this?

Thank.

EDIT:

What I would like to do is:

enter image description here

The image should not be blue at the top of the embankment. The image will be constantly updated with a lot of “blue” spots, the color should change depending on the external value, and ideally it will mix colors with previous points if they overlap.

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2 answers

Have you seen this from MATLAB technical support?

http://www.mathworks.com/support/solutions/en/data/1-GNRWEH/index.html

You can edit the properties colorbar.

g = colorbar;
get(g)

For instance,

% Define a colormap that uses the cool colormap and 
% the gray colormap and assign it as the Figure colormap.
colormap([cool(64);gray(64)])


% Generate some surface data.
[X,Y,Z] = peaks(30);


% Produce the two surface plots.
h(1) = surf(X,Y,Z);
hold on
h(2) = pcolor(X,Y,Z);
hold off


% Move the pcolor to Z = -10.
% The 0*Z is in the statement below to insure that the size
% of the ZData does not change.
set(h(2),'ZData',-10 + 0*Z)
set(h(2),'FaceColor','interp','EdgeColor','interp')
view(3)


% Scale the CData (Color Data) of each plot so that the 
% plots have contiguous, nonoverlapping values. The range 
% of each CData should be equal. Here the CDatas are mapped 
% to integer values so that they are easier to manage; 
% however, this is not necessary.


% Initially, both CDatas are equal to Z.
m = 64; % 64-elements is each colormap


cmin = min(Z(:));
cmax = max(Z(:));
% CData for surface
C1 = min(m,round((m-1)*(Z-cmin)/(cmax-cmin))+1); 
% CData for pcolor
C2 = 64+C1;


% Update the CDatas for each object.
set(h(1),'CData',C1);
set(h(2),'CData',C2);


% Change the CLim property of axes so that it spans the 
% CDatas of both objects.
caxis([min(C1(:)) max(C2(:))])

% I added these two lines
g = colorbar
set(g,'YLim',[1 60])

- . MATLAB. . , set(g,'YLim',[64 128]).

enter image description here

+2

, FaceColor. :

%# make some test data
[xx,yy]=ndgrid(-5:0.1:5,-5:0.1:5);
zz = exp(-xx.^2/2+-yy.^2/2);
zz1 = zz;
zz1(zz1>0.5)=NaN;
zz2 = zz;
zz2(zz2<0.5)=NaN;

%# plot first surface, set colormap
surf(zz1)
colormap('gray')

%# stretch colormap to [0 0.5]
caxis([0 0.5])

%# plot the second surface in red
hold on
surf(zz2,'faceColor','r')

enter image description here

, 'CData' . , , - , , .

%# make some more test data
[xx,yy]=ndgrid(-5:0.1:5,-5:0.1:5);
zz = exp(-xx.^2/2+-yy.^2/2);
zz1 = zz(1:50,:);
zz2 = zz(52:end,:);
xx1 = xx(1:50,:);xx2=xx(52:end,:);
yy1 = yy(1:50,:);yy2=yy(52:end,:);

%# create multi-colormap, set it to figure
figure
cmap = [gray(128);copper(128)];
colormap(cmap)

%# plot surfaces, setting the cdata property to indices 1-128 and 129-256, 
%# respectively, in order to access the different halves of the colormap
surf(xx1,yy1,zz1,'cdata',round(127*(zz1-min(zz1(:))/(max(zz1(:))-min(zz1(:)))))+1,'cdatamapping','direct')
hold on
surf(xx2,yy2,zz2,'cdata',round(127*(zz2-min(zz2(:))/(max(zz2(:))-min(zz2(:)))))+129,'cdatamapping','direct')

%# find the handle to the colorbar
%# alteratively: cbarH = findall(gcf,'tag','Colorbar')
cbarH = colorbar;

%# set limits and ticks/labels
ylim(cbarH,[129 255])
set(cbarH,'ytick',[129 192 255],'yticklabel',[0 0.5 1])

enter image description here

+7

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