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FYI, I received this warning for this code being a future error (Lecture 26)
UG[i] = U[c]
DeprecationWarning: Conversion of an array with ndim > 0 to a scalar is deprecated, and will error in future. Ensure you extract a single element from your array before performing this operation. (Deprecated NumPy 1.25.)
UG[i] = U[c]