[R] Creating the mean using algebra matrix

[Rolf Turner]

On 12/10/11 08:31, Timothy Bates wrote:
> To do matrix multiplication: m x n, the Rows and columns of  m must be equal to the columns and rows of n, respectively.

No.  The number of columns of m must equal the number of rows of n,
that's all.  The number of *rows* of m and the number of *columns* of n
can be anything you like.

     cheers,

         Rolf Turner