[Numpy-discussion] Extending ufunc signature syntax for matmul, frozen dimensions

[Marten van Kerkwijk]

I thought a bit further about this proposal: a disadvantage for matmul
specifically is that is does not solve the need for `matvec`,
`vecmat`, and `vecvec` gufuncs. That said, it might make sense to
implement those as "pseudo-ufuncs" that just add a 1 in the right
place and call `matmul`...
-- Marten