ColorBar ignore range with blank color

Hello!,

I have created one graph with colorbar ignoring certain range. I have replaced values in specified range for NAN values and automatically these values are displayed in blank, but not in the color bar. I would like to see the specified range in blank in the colorbar.

I have tried to modify the map matrix colors to [1 1 1] looking for the values considering nº of values and color bar limits, but is not working because I do not know how find the exactly position (rows) of the map matrix. The next code is not working with precision.

if threshold >0
    threshold=1/(colourbar_limit/threshold);
    min=round((length(map)/2)-((length(map)/2)*(threshold)));
    max=round((length(map)/2)+((length(map)/2)*(threshold)));
    for i=min:max
        map(i,:) = [1 1 1];    % set that position to white (light green around zero)
    end
else  
end

Answer 1

[Marc Jakobi]

I had a similar problem once. I can't find the script I had the solution in, but what I did was set the NaNs to a number smaller than the smallest number in the data, e. g.

data(isnan(data)) = -1;

or

data(isnan(data)) = min(data{:)) - 1;

Then I defined my colormap by adding white at the beginning:

customcmap = [(1 1 1); jet]; %you can use any colormap instead of jet here
colormap(customcmap)

[sara_game7]

Thank you for you answer but this is not a possible solution for me. I have values from -100 to 100 and sometimes the values to be ignored is the range -5 to 5. So I need to see in the colorbar the blank range -5 to 5. thank you.

[Marc Jakobi]

Then I would change the values between -5 to 5 to -101 and then change the TickLabels of the colorbar

data(data >= -5 && data <= 5) = -101
cmap = [(1 1 1); jet];
colormap(cmap)
cbr = colorbar;
tl = get(cbr, 'TickLabels');
tl{1} = 'NaN' % blank range indicator as string
set(cbr, 'TickLabels', tl)

[Anil Kumar]

Dear Marc,

is it possible to fill colorbar with white sapace after

max(data1)

for the first plot (say), in order to make equal range for the colorbars axis of the two plots with

max(data2)>>max(data1)

Thanks...