Performs a matrix-vector product of the matrix mat and the vector vec. The vector input is added to the final result.
If mat is a (n×m) tensor, vec is a 1-D tensor of size m, then input must be broadcastable with a 1-D tensor of size n and out will be 1-D tensor of size n.
alpha and beta are scaling factors on matrix-vector product between mat and vec and the added tensor input respectively.
\mboxout=β\mboxinput+α(\mboxmat@\mboxvec)
For inputs of type FloatTensor or DoubleTensor, arguments beta and alpha must be real numbers, otherwise they should be integers