Editing colors in a colormap

In my code, I'm using the imagesc function to create a changing colormap as a movie. I have created a manual map that goes from the white to black scale. However, there are certain parts of the colormap that I would like to manually make a color that does not fall in the white to black range, such as blue. I need to do this within my code, so that the code can capture the image as a frame. How would I accomplish this?

Thank you.

Answer 1

[Adam]

How do you have your colourmap currently? If you have it as an e.g. 256x3 matrix of colours then you can just set e.g.

myColourmap( 100,: ) = [0 0 1];

to make the 100th index colour blue.

[Shivani Patel]

map = [0 0 0

0.1 0.1 0.1

0.2 0.2 0.2

0.3 0.3 0.3

0.4 0.4 0.4

0.5 0.5 0.5

0.6 0.6 0.6

0.7 0.7 0.7

0.8 0.8 0.8

0.9 0.9 0.9

1 1 1];

% g1 to g17 change for each iteration and can range from 0-1

M=[g1 g2; g3 g4; g5 g6; g7 g8; g9 g10; g11 g12; g13 dum; g14 dum; g15 dum; g16 dum; g17 dum];

imagesc(M)

colormap(map)

caxis([0 1]);

frame = getframe(gcf);

For each variable 'dum' I need it to be manually set to a single color (that is not in the white to black range) so that it can be distinguishable. I'm still unsure as to how to do this.

Thanks.