Should vecdot accept keepdims? axis tuples?

[mdhaber]

I'm working on a PR for SciPy that replaces the sum(x * y) pattern with vecdot(x, y), since there are pretty substantial performance advantages. There is at least one place where the code currently relies on the keepdims argument of sum. Should that be accepted by vecdot?

How about axis tuples? I understand this does not look ideal, and I would also be happy if axis tuples were never allowed. But the motivation is the same - there are existing functions that use sum(x * y) and support axis tuples. If vecdot doesn't allow them, these functions all have to manually ravel the axes of x and y separately. (This operation can be moved into a helper function if need be, but hopefully it need not be.)