Evaluate a 2-D Chebyshev series at points (x, y).
This function returns the values:
The parameters x and y are converted to arrays only if they are tuples or a lists, otherwise they are treated as a scalars and they must have the same shape after conversion. In either case, either x and y or their elements must support multiplication and addition both with themselves and with the elements of c.
If c is a 1-D array a one is implicitly appended to its shape to make it 2-D. The shape of the result will be c.shape[2:] + x.shape.
x, y : array_like, compatible objects
c : array_like
values : ndarray, compatible object