How to interpolate vector data sets using interp2()

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I'm trying to use the interp2() function to interpolate a data point from a set of three vectors.
Vectors x, y, and z are all 10x1 and contain doubles. The data in vector z is assumed to correlate with a function of the data in vectors x and y, such that z = f(x, y).
How do I set up the interp2() to interpolate a value of z using any Xq and Yq that lie within the ranges of the x and y data sets?
I'm using the following code, which produces the error "Interpolation requires at least two sample points for each grid dimension."
x = [800; 900; 1000; 1100; 1200; 1300; 1400; 1500; 1600; 1700];
y = [30; 60; 90; 120; 150; 30; 60; 90; 120; 150];
z = [400; 330; 380; 240; 220; 380; 350; 270; 230; 215];
[X, Y] = meshgrid(x, y);
V = z;
Vq = interp2(X, Y, V, 1105, 130)
Error using griddedInterpolant
Interpolation requires at least two sample points for each grid dimension.

Error in interp2>makegriddedinterp (line 226)
F = griddedInterpolant(varargin{:});

Error in interp2 (line 134)
F = makegriddedinterp(X, Y, V, method,extrap);

Accepted Answer

Voss
Voss on 2 Apr 2024
You can't use interp2 with those vectors because they don't define a grid. You can use scatteredInterpolant instead.
x = [800; 900; 1000; 1100; 1200; 1300; 1400; 1500; 1600; 1700];
y = [30; 60; 90; 120; 150; 30; 60; 90; 120; 150];
z = [400; 330; 380; 240; 220; 380; 350; 270; 230; 215];
I = scatteredInterpolant(x,y,z);
Vq = I(1105, 130)
Vq = 216.2827

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