Plot 2D data colormap

Hello,

I have a file with 3 columns: x,y and z and I would like to plot a 2D map with the value of data z at the coordinate (x,y) with a colorbar that is in the range of the z-data (z is not a function of x and y). My points are from an unscructured grid point. I already try to use scatter and pcolor but I did not succeed to do this.

Could you help me to do this ? Thank you in advance !!

Camille From Belgium

[Bobby Fischer]

This could help:

x = -3 + 6*rand(50,1);
y = -3 + 6*rand(50,1);
v = sin(x).^4 .* cos(y);

F = scatteredInterpolant(x,y,v);
[xq,yq] = meshgrid(-3:0.1:3);

F.Method = 'linear';
vq1 = F(xq,yq);
figure(1), close(1), figure(1)
plot3(x,y,v,'mo')
hold on
mesh(xq,yq,vq1)
title('Nearest Neighbor')
legend('Sample Points','Interpolated Surface','Location','NorthWest')
view(2)
colormap default
colorbar

https://www.mathworks.com/help/matlab/visualize/representing-a-matrix-as-a-surface.html#f0-9140

https://es.mathworks.com/help/matlab/ref/scatteredinterpolant.html

[darova]

Better be to place your comment in the answer section

[Bobby Fischer]

Okay.

Answer 1

[Bobby Fischer]

This could help:

x = -3 + 6*rand(50,1);
y = -3 + 6*rand(50,1);
v = sin(x).^4 .* cos(y);

F = scatteredInterpolant(x,y,v);
[xq,yq] = meshgrid(-3:0.1:3);

F.Method = 'linear';
vq1 = F(xq,yq);
figure(1), close(1), figure(1)
plot3(x,y,v,'mo')
hold on
mesh(xq,yq,vq1)
title('Nearest Neighbor')
legend('Sample Points','Interpolated Surface','Location','NorthWest')
view(2)
colormap default
colorbar

https://www.mathworks.com/help/matlab/visualize/representing-a-matrix-as-a-surface.html#f0-9140

https://es.mathworks.com/help/matlab/ref/scatteredinterpolant.html

[Nathan Hardenberg]

% Result: