 R and the number of rows
          of the matrix op( A ).  M &gt;= 0.

  N       (input) INTEGER
          The order of the matrix X and the number of columns of the
          the matrix op( A ).  N &gt;= 0.

  ALPHA   (input) DOUBLE PRECISION
          The scalar alpha. When alpha is zero then R need not be
          set before entry, except when R is identified with X in
          the call (which is possible only in this case).

  BETA    (input) DOUBLE PRECISION
          The scalar beta. When beta is z