The FORTRAN level-2 BLAS call for this operation is
Here is replaced by S, D, C, or Z to indicate the datatype of the data (single, double, complex, double precision complex). Parameter TRANS indicates if A is to be (conjugate) transposed in the operation and can take on values "No transpose", "Transpose", or "Conjugate transpose". Parameters M and N hold the matrix dimensions m and n , respectively. Parameters ALPHA and BETA hold the scaling factors and . Parameters A, X, and Y equal the addresses of where matrix A and vectors x , and y start in memory. The leading dimensions of the matrix is given in LDA and the strides for the vectors in INCX and INCY.SUBROUTINE GEMV ( TRANS, M, N, ALPHA, A, LDA, X, INCX, BETA, Y, INCY )