The 'TriScatteredInterp' function does not perform any extrapolation, whereas the 'scatteredInterpolant' function performs extrapolation by default.
Specifically, the 'scatteredInterpolant' function defaults to the extrapolation method of 'linear' when the interpolation method is 'linear' or 'natural' and the extrapolation method of 'nearest' when the interpolation method is 'nearest,' as described in the documentation found below under 'ExtrapolationMethod':
This can be resolved by manually setting the extrapolation method to 'none' in the call to 'scatteredInterpolant.' For example, the following lines of code should produce the same result for vectors x, y, and v:
>>scatteredInterpolant(x, y, v, 'linear', 'none')
>>TriScatteredInterp(x, y, v, 'linear')
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