How can I specify different colors for different groups of data in correlation heatmap?

Hello,

I have a correlation heatmap and I would like all the "boxes" with -0.7<R<0.7 to be the same color (e.g. gray), so to be able to more easily visualize the others.

To do this for only one range (e.g. R<0.7), I used caxis, but it does not allow to specify multiple ranges.

This looks like it would be an easy fix, but I am pretty new to Matlab and I don't seem to be able to figure out anything.

Thanks for your input!

Rosalba

[darova]

Maybe you are looking for this

ix = x.^2 + y.^2 < 0.7^2;       % find indices inside radius
A(ix) = 0.5;                    % assign 0.5 value inside
imagesc(A)

[Rosalba Gaudiuso]

Hi,

Thanks for your answer.

I ended up setting all the -0.7<R<0.7 values = 0 with a relational operator and then just plotting the heatmap as such.

Definitely not the most elegant solution, but for a total beginner it kinda works. :)

[darova]

ok

Answer 1

[Devineni Aslesha]

Hi Rosalba,

Here is the way to map the boxes with range -0.7<R<0.7 to the same colour.

load patients
tbl = table(LastName,Age,Gender,SelfAssessedHealthStatus,...
    Smoker,Weight,Location);
h = heatmap(tbl,'Smoker','SelfAssessedHealthStatus','ColorVariable','Age','ColorMethod','median');
xh = h.Colormap > -0.7 & h.Colormap < 0.7;
[rowIdx, colIdx] = find(xh == 1);
h.Colormap(rowIdx, colIdx) = 0.5;

For more information, refer the following links.

https://www.mathworks.com/help/matlab/ref/heatmap.html

https://www.mathworks.com/help/matlab/ref/find.html

[Rosalba Gaudiuso]

Thank you!