is this a typo in the doc of matmul!

[JianghuiDu]

matmul!(C, A, B[, α, β, max_threads])
Calculates C = α * A * B + β * C in place, overwriting the contents of A. 

overwriting the contents of A.

Not C? Also why is there a bracket in side?

[chriselrod]

Yes, it is a typo. It overwrites the contents of C, not of A.

The brackets meant to say that those are optional positional arguments. Perhaps it should instead show their defaults to make that more clear.

[JianghuiDu]

Also I noticed that C, A and B must all be matrix in matmul!. Whereas the LinearAlgebra mul! accepts vectors for C and B. Is there a plan to support matrix vector multiplication?

[chriselrod]

Yes. It should be much simpler than matrix-matrix.