Legend with 15 colors

Hello,

How can I make a 3D plot legend to have 15 colors/levels and seperated/discreet like the attached example?

Thanks in advance!

Answer 1

[Star Strider]

Try this —

x = linspace(0, sqrt(300), 15);
y = x;
z = x(:)*y;

figure
surf(1:15, 1:15, z)
grid on
colormap(turbo(15))
colorbar

I am not certain what colormap was used in the posted question. I chose turbo here.

Experiment with the actual data.

.

[Ash Ahamed]

Thank you!

[Star Strider]

As always, my pleasure!

.

Answer 2

[DGM]

I don't know what your plot type is, but consider the contourf example:

% the given colormap
cmap = [0.851 0.851 0.851;0.498 1 1;0.298 0.8 1;0 0.6196 1;0 0 0.9529;0.498 1 0.498;0.09804 1 0.09804;0.09804 0.6 0.09804;1 0.749 1;1 0.4 1;0.8 0.09804 1;1 1 0;1 0.651 0;0.9529 0.298 0;0.8 0 0];

% dummy data
x = linspace(0,1,100);
y = x.';
z = max(x,y);

% plot setup
contourf(x,y,z,size(cmap,1)-1)
axis equal
colormap(cmap)

% wrangle the colorbar tick alignment
cb = colorbar;

cbscalein = cb.Limits;
cbscaleout = [min(z(:)) max(z(:))];

ticks = linspace(cbscaleout(1),cbscaleout(2),size(cmap,1)+1);
cb.Ticks = diff(cbscalein)*(ticks-cbscaleout(1))/diff(cbscaleout) + cbscalein(1);
cb.TickLabels = diff(cbscaleout)*(cb.Ticks-cbscalein(1))/diff(cbscalein) + cbscaleout(1);

That may be able to be simplified, but I'll leave that to someone else to reveal.

[Ash Ahamed]

Thank you! your solution works perfect as well.