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      SUBROUTINE CHEMM(SIDE,UPLO,M,N,ALPHA,A,LDA,B,LDB,BETA,C,LDC)
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*     .. Scalar Arguments ..
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      COMPLEX ALPHA,BETA
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      INTEGER LDA,LDB,LDC,M,N
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      CHARACTER SIDE,UPLO
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*     ..
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*     .. Array Arguments ..
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      COMPLEX A(LDA,*),B(LDB,*),C(LDC,*)
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*     ..
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*
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*  Purpose
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*  =======
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*
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*  CHEMM  performs one of the matrix-matrix operations
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*
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*     C := alpha*A*B + beta*C,
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*
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*  or
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*
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*     C := alpha*B*A + beta*C,
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*
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*  where alpha and beta are scalars, A is an hermitian matrix and  B and
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*  C are m by n matrices.
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*
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*  Arguments
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*  ==========
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*
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*  SIDE   - CHARACTER*1.
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*           On entry,  SIDE  specifies whether  the  hermitian matrix  A
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*           appears on the  left or right  in the  operation as follows:
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*
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*              SIDE = 'L' or 'l'   C := alpha*A*B + beta*C,
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*
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*              SIDE = 'R' or 'r'   C := alpha*B*A + beta*C,
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*
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*           Unchanged on exit.
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*
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*  UPLO   - CHARACTER*1.
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*           On  entry,   UPLO  specifies  whether  the  upper  or  lower
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*           triangular  part  of  the  hermitian  matrix   A  is  to  be
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*           referenced as follows:
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*
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*              UPLO = 'U' or 'u'   Only the upper triangular part of the
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*                                  hermitian matrix is to be referenced.
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*
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*              UPLO = 'L' or 'l'   Only the lower triangular part of the
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*                                  hermitian matrix is to be referenced.
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*
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*           Unchanged on exit.
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*
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*  M      - INTEGER.
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*           On entry,  M  specifies the number of rows of the matrix  C.
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*           M  must be at least zero.
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*           Unchanged on exit.
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*
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*  N      - INTEGER.
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*           On entry, N specifies the number of columns of the matrix C.
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*           N  must be at least zero.
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*           Unchanged on exit.
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*
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*  ALPHA  - COMPLEX         .
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*           On entry, ALPHA specifies the scalar alpha.
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*           Unchanged on exit.
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*
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*  A      - COMPLEX          array of DIMENSION ( LDA, ka ), where ka is
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*           m  when  SIDE = 'L' or 'l'  and is n  otherwise.
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*           Before entry  with  SIDE = 'L' or 'l',  the  m by m  part of
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*           the array  A  must contain the  hermitian matrix,  such that
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*           when  UPLO = 'U' or 'u', the leading m by m upper triangular
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*           part of the array  A  must contain the upper triangular part
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*           of the  hermitian matrix and the  strictly  lower triangular
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*           part of  A  is not referenced,  and when  UPLO = 'L' or 'l',
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*           the leading  m by m  lower triangular part  of the  array  A
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*           must  contain  the  lower triangular part  of the  hermitian
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*           matrix and the  strictly upper triangular part of  A  is not
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*           referenced.
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*           Before entry  with  SIDE = 'R' or 'r',  the  n by n  part of
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*           the array  A  must contain the  hermitian matrix,  such that
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*           when  UPLO = 'U' or 'u', the leading n by n upper triangular
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*           part of the array  A  must contain the upper triangular part
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*           of the  hermitian matrix and the  strictly  lower triangular
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*           part of  A  is not referenced,  and when  UPLO = 'L' or 'l',
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*           the leading  n by n  lower triangular part  of the  array  A
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*           must  contain  the  lower triangular part  of the  hermitian
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*           matrix and the  strictly upper triangular part of  A  is not
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*           referenced.
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*           Note that the imaginary parts  of the diagonal elements need
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*           not be set, they are assumed to be zero.
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*           Unchanged on exit.
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*
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*  LDA    - INTEGER.
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*           On entry, LDA specifies the first dimension of A as declared
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*           in the  calling (sub) program. When  SIDE = 'L' or 'l'  then
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*           LDA must be at least  max( 1, m ), otherwise  LDA must be at
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*           least max( 1, n ).
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*           Unchanged on exit.
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*
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*  B      - COMPLEX          array of DIMENSION ( LDB, n ).
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*           Before entry, the leading  m by n part of the array  B  must
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*           contain the matrix B.
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*           Unchanged on exit.
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*
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*  LDB    - INTEGER.
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*           On entry, LDB specifies the first dimension of B as declared
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*           in  the  calling  (sub)  program.   LDB  must  be  at  least
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*           max( 1, m ).
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*           Unchanged on exit.
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*
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*  BETA   - COMPLEX         .
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*           On entry,  BETA  specifies the scalar  beta.  When  BETA  is
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*           supplied as zero then C need not be set on input.
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*           Unchanged on exit.
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*
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*  C      - COMPLEX          array of DIMENSION ( LDC, n ).
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*           Before entry, the leading  m by n  part of the array  C must
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*           contain the matrix  C,  except when  beta  is zero, in which
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*           case C need not be set on entry.
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*           On exit, the array  C  is overwritten by the  m by n updated
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*           matrix.
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*
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*  LDC    - INTEGER.
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*           On entry, LDC specifies the first dimension of C as declared
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*           in  the  calling  (sub)  program.   LDC  must  be  at  least
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*           max( 1, m ).
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*           Unchanged on exit.
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*
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*
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*  Level 3 Blas routine.
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*
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*  -- Written on 8-February-1989.
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*     Jack Dongarra, Argonne National Laboratory.
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*     Iain Duff, AERE Harwell.
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*     Jeremy Du Croz, Numerical Algorithms Group Ltd.
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*     Sven Hammarling, Numerical Algorithms Group Ltd.
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*
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*
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*     .. External Functions ..
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      LOGICAL LSAME
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      EXTERNAL LSAME
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*     ..
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*     .. External Subroutines ..
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      EXTERNAL XERBLA
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*     ..
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*     .. Intrinsic Functions ..
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      INTRINSIC CONJG,MAX,REAL
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*     ..
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*     .. Local Scalars ..
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      COMPLEX TEMP1,TEMP2
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      INTEGER I,INFO,J,K,NROWA
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      LOGICAL UPPER
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*     ..
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*     .. Parameters ..
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      COMPLEX ONE
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      PARAMETER (ONE= (1.0E+0,0.0E+0))
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      COMPLEX ZERO
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      PARAMETER (ZERO= (0.0E+0,0.0E+0))
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*     ..
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*
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*     Set NROWA as the number of rows of A.
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*
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      IF (LSAME(SIDE,'L')) THEN
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          NROWA = M
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      ELSE
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          NROWA = N
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      END IF
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      UPPER = LSAME(UPLO,'U')
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*
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*     Test the input parameters.
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*
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      INFO = 0
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      IF ((.NOT.LSAME(SIDE,'L')) .AND. (.NOT.LSAME(SIDE,'R'))) THEN
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          INFO = 1
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      ELSE IF ((.NOT.UPPER) .AND. (.NOT.LSAME(UPLO,'L'))) THEN
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          INFO = 2
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      ELSE IF (M.LT.0) THEN
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          INFO = 3
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      ELSE IF (N.LT.0) THEN
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          INFO = 4
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      ELSE IF (LDA.LT.MAX(1,NROWA)) THEN
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          INFO = 7
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      ELSE IF (LDB.LT.MAX(1,M)) THEN
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          INFO = 9
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      ELSE IF (LDC.LT.MAX(1,M)) THEN
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          INFO = 12
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      END IF
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      IF (INFO.NE.0) THEN
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          CALL XERBLA('CHEMM ',INFO)
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          RETURN
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      END IF
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*
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*     Quick return if possible.
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*
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      IF ((M.EQ.0) .OR. (N.EQ.0) .OR.
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     +    ((ALPHA.EQ.ZERO).AND. (BETA.EQ.ONE))) RETURN
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*
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*     And when  alpha.eq.zero.
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*
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      IF (ALPHA.EQ.ZERO) THEN
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          IF (BETA.EQ.ZERO) THEN
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              DO 20 J = 1,N
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                  DO 10 I = 1,M
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                      C(I,J) = ZERO
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   10             CONTINUE
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   20         CONTINUE
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          ELSE
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              DO 40 J = 1,N
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                  DO 30 I = 1,M
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                      C(I,J) = BETA*C(I,J)
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   30             CONTINUE
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   40         CONTINUE
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          END IF
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          RETURN
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      END IF
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*
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*     Start the operations.
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*
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      IF (LSAME(SIDE,'L')) THEN
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*
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*        Form  C := alpha*A*B + beta*C.
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*
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          IF (UPPER) THEN
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              DO 70 J = 1,N
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                  DO 60 I = 1,M
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                      TEMP1 = ALPHA*B(I,J)
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                      TEMP2 = ZERO
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                      DO 50 K = 1,I - 1
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                          C(K,J) = C(K,J) + TEMP1*A(K,I)
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                          TEMP2 = TEMP2 + B(K,J)*CONJG(A(K,I))
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   50                 CONTINUE
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                      IF (BETA.EQ.ZERO) THEN
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                          C(I,J) = TEMP1*REAL(A(I,I)) + ALPHA*TEMP2
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                      ELSE
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                          C(I,J) = BETA*C(I,J) + TEMP1*REAL(A(I,I)) +
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     +                             ALPHA*TEMP2
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                      END IF
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   60             CONTINUE
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   70         CONTINUE
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          ELSE
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              DO 100 J = 1,N
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                  DO 90 I = M,1,-1
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                      TEMP1 = ALPHA*B(I,J)
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                      TEMP2 = ZERO
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                      DO 80 K = I + 1,M
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                          C(K,J) = C(K,J) + TEMP1*A(K,I)
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                          TEMP2 = TEMP2 + B(K,J)*CONJG(A(K,I))
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   80                 CONTINUE
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                      IF (BETA.EQ.ZERO) THEN
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                          C(I,J) = TEMP1*REAL(A(I,I)) + ALPHA*TEMP2
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                      ELSE
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                          C(I,J) = BETA*C(I,J) + TEMP1*REAL(A(I,I)) +
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     +                             ALPHA*TEMP2
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                      END IF
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   90             CONTINUE
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  100         CONTINUE
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          END IF
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      ELSE
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*
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*        Form  C := alpha*B*A + beta*C.
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*
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          DO 170 J = 1,N
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              TEMP1 = ALPHA*REAL(A(J,J))
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              IF (BETA.EQ.ZERO) THEN
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                  DO 110 I = 1,M
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                      C(I,J) = TEMP1*B(I,J)
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  110             CONTINUE
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              ELSE
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                  DO 120 I = 1,M
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                      C(I,J) = BETA*C(I,J) + TEMP1*B(I,J)
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  120             CONTINUE
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              END IF
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              DO 140 K = 1,J - 1
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                  IF (UPPER) THEN
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                      TEMP1 = ALPHA*A(K,J)
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                  ELSE
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                      TEMP1 = ALPHA*CONJG(A(J,K))
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                  END IF
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                  DO 130 I = 1,M
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                      C(I,J) = C(I,J) + TEMP1*B(I,K)
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  130             CONTINUE
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  140         CONTINUE
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              DO 160 K = J + 1,N
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                  IF (UPPER) THEN
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                      TEMP1 = ALPHA*CONJG(A(J,K))
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                  ELSE
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                      TEMP1 = ALPHA*A(K,J)
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                  END IF
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                  DO 150 I = 1,M
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                      C(I,J) = C(I,J) + TEMP1*B(I,K)
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  150             CONTINUE
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  160         CONTINUE
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  170     CONTINUE
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      END IF
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*
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      RETURN
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*
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*     End of CHEMM .
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*
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      END