Colorbar with a range taken from a variable

Hello,

I have a matrix organized in this way:

M= col1, col2.... col10

col1 and col2 are the x and y position of the data, col10 is a property of this data and it is a number.

I would like to use the numbers in col10 to make a colormap and assign ot every point a specific color that depends on the value in col10.

I did this long time ago, but I don't remember how, can somebody help me, please?

Thanks

F.

Answer 1

[Star Strider]

I am not certain what plot you want to use or what result you want.

Perhaps something like this —

x = linspace( 0, 5);
y = linspace(-5, 5);
z = exp(-((x-2.5).^2 + y.^2));

figure
scatter3(x, y, z, 25, z, 'filled')
colormap(turbo)
colorbar
view(45,30)

x = randn(1, 1000);
y = randn(1, 1000);
z = exp(-(x.^2 + y.^2));

figure
scatter3(x, y, z, 25, z, 'filled')
colormap(turbo)
colorbar

.

[Francesco]

YES!!!

I did it, thanks!

figure(1)

scatter(L01(:,2),L01(:,3),[],L01(:,10)/10^6,'+')

colorbar

xlim([-20 20])

ylim([-20 20])

xlabel('x [mm]')

ylabel('y-[mm]')

title('Gaf n. 1')

[Francesco]

is it correct like this?

[Star Strider]

As always, my pleasure!

Yes! That is correct. The syntax depends on the plot you want. For a 2D scatter plot, the fourth argument defines the colour of the markers.

[Francesco]

Thanks a lot Star Strider,

If what I wrote is ok than your example helped my memory a lot!

Cheers

[Star Strider]

As always, my pleasure!

Thank you!

Answer 2

[Rahul Chowdhury]

Try something like

M = [col1; col2; col10];
contourf(M, col10)
colorbar('Ticks', col10)

This creates a contour plot with the specific levels from col10 and while labeling them in a color bar. Let me know if this helps.