How to change color of colorbar's lower minimum value?

How can I change the minimum value color on the color bar? I'm getting white color for the lower values.

imagesc(x,y,value)
set(gca,'YDir','normal')
myColorMap = colormap;
myColorMap(1,:) = [1 1 1];
colormap(myColorMap);
colorbar;
ma=max(value);
mi=min(value);

Answer 1

[Star Strider]

You are getting a white color for the lower values because you defined:

myColorMap(1,:) = [1 1 1];

[Andrew Reibold]

Correct

[Star Strider]

Thank you!

[Tunechi]

Thank you for your response, That would work but it gives same color to masked area(NaN) values and zero values. is there away to ignore NaN values from the plot?

value(find(Maskvalue==0))=nan

[Star Strider]

The NaN values shouldn’t plot. To the best of my knowledge, all the plot functions simply ignore them.

[Tunechi]

If that the case, my question would be how to change the background color to white which is outside the value matrix

[Star Strider]

I’m not certain I understand what you’re referring to.

You can ‘pad’ the colormap on the high and low ends with white:

x = randi(100, 50, 50);
x(x==1) = NaN;

h = colormap(jet(10));
z = ones(14,3); 
z(3:12,:) = h;          % Pad With White
h = z;

figure(1)
contourf(x)

The NaN values will continue to be blank because the plot will ignore them.

[Tunechi]

Definitely it worked in your case. please have look at the attached files. Many Thanks

[Star Strider]

The matfile function tells me that these are (72x166) double arrays.

What are they?

What do you want me to do with them?

[Tunechi]

Star Stider, thank you very much for your help. I was using imagesc to plot my values and the problem was imagesc doesn't skip nan values. I found a function that modify imagesc to skip nan values. http://www.mathworks.ca/matlabcentral/fileexchange/20516-imagescnan-m-v2-1--aug-2009-

[Image Analyst]

Why does your image have nan's in it anyway? What color do you want the nan's to appear as? I think an axes control might have a background or foreground color that appears if the pixels are nan's (so they mgiht be "transparent") but I'd have to check on that. I never deal with images that have nan's. Why do you have them?

[Star Strider]

Tunechi — My pleasure!

I A — That’s new. I didn’t know about imagesc until now. I used contourf in my example.