crossprod.Rd
Given matrices x
and y
as arguments, return a matrix
cross-product. This is formally equivalent to (but usually
slightly faster than) the call t(x) %*% y
(crossprod.spam
) or x
%*% t(y)
(tcrossprod.spam
).
crossprod.spam(x, y = NULL, ...)
tcrossprod.spam(x, y = NULL, ...)
matrices: y = NULL
is taken to be the
same matrix as x
. Vectors are promoted to single-column or
single-row matrices, depending on the context.
potentially further arguments from other methods.
A double matrix
When x
or y
are not matrices, they are treated as column or
row matrices.
crossprod.spam(diag.spam(2),1:2)
#> [,1]
#> [1,] 1
#> [2,] 2