ARCHIVED: Plot irregularly spaced data in MATLAB

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To plot irregularly spaced data in MATLAB, use the TriScatteredInterp command to create a data structure for interpolation.

The example below plots a saddle-shaped surface by interpolating over 100 random data points:

%Pick random x and y coordinates
%  and compute z values.
x = rand(100,1)*10-5;
y = rand(100,1)*10-5;

z = x.^2 -y.^2;

%Construct the interpolant and use to evaluate
%  zi for values (xi,yi)
F = TriScatteredInterp(x,y,z);
ti = -5:.1:5;

[xi,yi] = meshgrid(ti,ti);
zi = F(xi,yi);

%Plot the interpolated surface in black
plot3(xi,yi,zi,'k');

%Add the original data points in red
hold on; plot3(x,y,z,'or'); hold off

If you have questions about using statistical and mathematical software at Indiana University, contact the UITS Research Applications and Deep Learning team.

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Last modified on 2023-10-05 16:49:47.