ZHEMM  performs one of the matrix-matrix operations


    C := alpha*A*B + beta*C,


 or


    C := alpha*B*A + beta*C,


 where alpha and beta are scalars, A is an hermitian matrix and  B and


 C are m by n matrices.

SIDE

          SIDE is CHARACTER*1


           On entry,  SIDE  specifies whether  the  hermitian matrix  A


           appears on the  left or right  in the  operation as follows:


              SIDE = 'L' or 'l'   C := alpha*A*B + beta*C,


              SIDE = 'R' or 'r'   C := alpha*B*A + beta*C,

UPLO

          UPLO is CHARACTER*1


           On  entry,   UPLO  specifies  whether  the  upper  or  lower


           triangular  part  of  the  hermitian  matrix   A  is  to  be


           referenced as follows:


              UPLO = 'U' or 'u'   Only the upper triangular part of the


                                  hermitian matrix is to be referenced.


              UPLO = 'L' or 'l'   Only the lower triangular part of the


                                  hermitian matrix is to be referenced.

M

          M is INTEGER


           On entry,  M  specifies the number of rows of the matrix  C.


           M  must be at least zero.

N

          N is INTEGER


           On entry, N specifies the number of columns of the matrix C.


           N  must be at least zero.

ALPHA

          ALPHA is COMPLEX*16


           On entry, ALPHA specifies the scalar alpha.

A

          A is COMPLEX*16 array, dimension ( LDA, ka ), where ka is


           m  when  SIDE = 'L' or 'l'  and is n  otherwise.


           Before entry  with  SIDE = 'L' or 'l',  the  m by m  part of


           the array  A  must contain the  hermitian matrix,  such that


           when  UPLO = 'U' or 'u', the leading m by m upper triangular


           part of the array  A  must contain the upper triangular part


           of the  hermitian matrix and the  strictly  lower triangular


           part of  A  is not referenced,  and when  UPLO = 'L' or 'l',


           the leading  m by m  lower triangular part  of the  array  A


           must  contain  the  lower triangular part  of the  hermitian


           matrix and the  strictly upper triangular part of  A  is not


           referenced.


           Before entry  with  SIDE = 'R' or 'r',  the  n by n  part of


           the array  A  must contain the  hermitian matrix,  such that


           when  UPLO = 'U' or 'u', the leading n by n upper triangular


           part of the array  A  must contain the upper triangular part


           of the  hermitian matrix and the  strictly  lower triangular


           part of  A  is not referenced,  and when  UPLO = 'L' or 'l',


           the leading  n by n  lower triangular part  of the  array  A


           must  contain  the  lower triangular part  of the  hermitian


           matrix and the  strictly upper triangular part of  A  is not


           referenced.


           Note that the imaginary parts  of the diagonal elements need


           not be set, they are assumed to be zero.

LDA

          LDA is INTEGER


           On entry, LDA specifies the first dimension of A as declared


           in the  calling (sub) program. When  SIDE = 'L' or 'l'  then


           LDA must be at least  max( 1, m ), otherwise  LDA must be at


           least max( 1, n ).

B

          B is COMPLEX*16 array, dimension ( LDB, N )


           Before entry, the leading  m by n part of the array  B  must


           contain the matrix B.

LDB

          LDB is INTEGER


           On entry, LDB specifies the first dimension of B as declared


           in  the  calling  (sub)  program.   LDB  must  be  at  least


           max( 1, m ).

BETA

          BETA is COMPLEX*16


           On entry,  BETA  specifies the scalar  beta.  When  BETA  is


           supplied as zero then C need not be set on input.

C

          C is COMPLEX*16 array, dimension ( LDC, N )


           Before entry, the leading  m by n  part of the array  C must


           contain the matrix  C,  except when  beta  is zero, in which


           case C need not be set on entry.


           On exit, the array  C  is overwritten by the  m by n updated


           matrix.

LDC

          LDC is INTEGER


           On entry, LDC specifies the first dimension of C as declared


           in  the  calling  (sub)  program.   LDC  must  be  at  least


           max( 1, m ).

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

  Level 3 Blas routine.


  -- Written on 8-February-1989.


     Jack Dongarra, Argonne National Laboratory.


     Iain Duff, AERE Harwell.


     Jeremy Du Croz, Numerical Algorithms Group Ltd.


     Sven Hammarling, Numerical Algorithms Group Ltd.