Change colormap on contour plot.

I have a chart that looks like

Can anyone help me out with changing the color gradation so that the minimum value is red and the maximum value is blue?

Thank you so much!

Answer 1

[Walter Roberson]

colormap(flipud(jet))

This will have green and yellow and orange in the middle, but you didn't say it couldn't ;-)

If you only want red and blue, then you will need to describe how you want the colors to evolve. Is it acceptable to go through purple in the middle?

[Sung Yeob Lim]

Thanks for the response.

Essentially I want an RGB color gradation. So the red will go through green and then go onto blue.

[Walter Roberson]

N = size(colormap(),1);   %size of existing colormap
assert(mod(N,2) == 1, 'Code cannot handle colormap with even number of entries')
v = linspace(0,1,floor(N/2)+1);
v = v(1:end-1);   %throw out the 1 exactly
z = zeros(size(v));
r = [1, fliplr(v), 0, z, 0];
g = [v, 1, fliplr(v)];
b = [z, 0, v];
cmap = [r(:), g(:), b(:)];
colormap(cmap)

... Something like that. I am having a bit of trouble with the boundary conditions.

The colormap needs to be an odd size because the green in the center needs to be unique and presumably you want the red->green size to be the same as the green->blue size.