plotting a set of irregular data points

Hello,

I have a set of data points with columns as follows:

x(cart) | y(cart) | z(cart) | theta (sph) | phi (sph) | Intensity (dB)

cart = cartesian coordinates; sph=spherical coordinates

I want to plot these data points on a 3D plot where x-axis is theta, y-axis is phi, and color is the intensity.

If for example theta has values 0:5:180 degrees and for every theta value there are these phi values 0:10:360 degrees then I can arrange a matrix and use imagesc.

The problem with my set of data points is that the theta and phi values are irregular meaning they are scattered on a sphere. Some data points can have the same theta but different phi, some have same phi but different theta and other points may have unique theta and phi. Like I said, these are points are scattered on a sphere.

Is there any way I can plot these data points so that intensity will be represented by color?

Thank you.

Answer 1

[Luna]

Hi,

You can use scatter3 function to create a 3D scatter plot.

Check the link: scatter3

For coloring the intensity search for colormap and colorbar.

You can use predefined (Matlab's built-in) colormaps' each row according to your intensity data while looping in scatter. Something like this:

% data
[x, y] = meshgrid(1:100);
z = cos(x).^2 + sin(y).^2;
intensityVector = randi(20,numel(x),1);
c = jet(numel(x)); % create your own colormap here with Mx3 matrix

%xdata,ydata,zdata scatter plot, marker size 10, color is c Matrix
scatter3(x(:),y(:),z(:),10,c);
% define colomap and colorbar according the your colormap
colormap(c);
colorbar;

Answer 2

[Saeed Ghanbarifar]

how can i plot this map in matlab or python ?/

x=lat : utm system

y= long

z= magnetic data

[Luna]

Please use the "ask a question" section on that topic and explain properly what you have and what you need.