What does Field.vdot() do if the spaces keyword is present?
What is the expected result if we call
a.vdot(b,spaces=0)
where a is a Field living on one space and b is a Field living on two spaces?
I'm asking because the documentation says that the result should be float or complex, but the code actually returns a Field object.
Is there an undocumented constraint that both Fields must have the same number of domains?