Distinct NaN from other values in image

I want to plot image with different values and easily distinct them from NaN values. As default NaN values are imaged with the same color as the minimum value. I have tried a range of possibilites but each provide their own issue. Here is one example:

The solution from here, image all other values as one color

imagesc(CP)
sc(isnan(CP), 'bone', [1 1 1]);

[Agnete]

The NaN values outside of my shape should be one color (gray/white) but without changing the value of my polygon inside my shape (value 10-100). When I use imagesc(~isnan(CP)) the value of my polygons are overwritten with value of 1.

[Image Analyst]

The answer has been accepted. I don't see a question in the last comment. And no m-file was attached.

[Oliver Woodford]

You did not use sc correctly. Try:

   sc(CP, 'bone', 'r')

Answer 1

[Iain]

This can let you plot NaN & any other logically findable section of the image as white

 a = rand(5);
 a(3,3) = NaN;
 b = imagesc(a);
 set(b,'AlphaData',~isnan(a))

Alternatively, you can deliberately control the "colormap" settings to ensure that "invalid" values show up as a colour that isn't used by the colour map.

[Agnete]

At first I was taken back as the axis values was dublicated in a weird way as can be seen with the fig-format but fortunately this is resolved when saving as pdf-format. However when I use export_fig the original NaN-color returns!

[Andrea]

changed my life

[Dev Laxman Subramanian]

Works like a charm!

Answer 2

[Image Analyst]

I don't know what "plot" means when talking about an image. I don't know why you want to plot anything on an image, like markers to "cover up" the nan locations. Why not just set the nan's to the min gray level and view it like a normal image?

CP(isnan(CP)) = min(CP(:)); % Set nan values to the min value
image(CP);
colormap(bone(256));
colorbar;

[Agnete]

Nan values are imaged with the same color as my minimum value. I want to distinct between my minimum values and Nan.

Why I use add a plot of coordinates to my image is irrelevant in this context and I have now deleted that code in my original question.

[Agnete]

The problem is illustrated in the attached where it is seen that the polygon in northeast corner blends into the background

[Image Analyst]

Sorry but I don't understand this. One just sort of looks like a very blurred version of the other. Both have the same pattern of triangles on them, and I don't even know what a triangle means/represents. Your image is an array. You can't have nan values have the same value as your minimum value. An element can have only one value, either a nan or some number. It can't have both at the same time. So "Nan values are imaged with the same color as my minimum value" makes no sense to me.