      SUBROUTINE ZLASET( UPLO, M, N, ALPHA, BETA, A, LDA )
*
*  -- LAPACK auxiliary routine (version 2.0) --
*     Univ. of Tennessee, Univ. of California Berkeley, NAG Ltd.,
*     Courant Institute, Argonne National Lab, and Rice University
*     October 31, 1992
*
*     .. Scalar Arguments ..
      CHARACTER          UPLO
      INTEGER            LDA, M, N
      COMPLEX*16         ALPHA, BETA
*     ..
*     .. Array Arguments ..
      COMPLEX*16         A( LDA, * )
*     ..
*
*  Purpose
*  =======
*
*  ZLASET initializes a 2-D array A to BETA on the diagonal and
*  ALPHA on the offdiagonals.
*
*  Arguments
*  =========
*
*  UPLO    (input) CHARACTER*1
*          Specifies the part of the matrix A to be set.
*          = 'U':      Upper triangular part is set. The lower triangle
*                      is unchanged.
*          = 'L':      Lower triangular part is set. The upper triangle
*                      is unchanged.
*          Otherwise:  All of the matrix A is set.
*
*  M       (input) INTEGER
*          On entry, M specifies the number of rows of A.
*
*  N       (input) INTEGER
*          On entry, N specifies the number of columns of A.
*
*  ALPHA   (input) COMPLEX*16
*          All the offdiagonal array elements are set to ALPHA.
*
*  BETA    (input) COMPLEX*16
*          All the diagonal array elements are set to BETA.
*
*  A       (input/output) COMPLEX*16 array, dimension (LDA,N)
*          On entry, the m by n matrix A.
*          On exit, A(i,j) = ALPHA, 1 <= i <= m, 1 <= j <= n, i.ne.j;
*                   A(i,i) = BETA , 1 <= i <= min(m,n)
*
*  LDA     (input) INTEGER
*          The leading dimension of the array A.  LDA >= max(1,M).
*
*  =====================================================================
*
*     .. Local Scalars ..
      INTEGER            I, J
*     ..
*     .. External Functions ..
      LOGICAL            LSAME
      EXTERNAL           LSAME
*     ..
*     .. Intrinsic Functions ..
      INTRINSIC          MIN
*     ..
*     .. Executable Statements ..
*
      IF( LSAME( UPLO, 'U' ) ) THEN
*
*        Set the diagonal to BETA and the strictly upper triangular
*        part of the array to ALPHA.
*
         DO 20 J = 2, N
            DO 10 I = 1, MIN( J-1, M )
               A( I, J ) = ALPHA
   10       CONTINUE
   20    CONTINUE
         DO 30 I = 1, MIN( N, M )
            A( I, I ) = BETA
   30    CONTINUE
*
      ELSE IF( LSAME( UPLO, 'L' ) ) THEN
*
*        Set the diagonal to BETA and the strictly lower triangular
*        part of the array to ALPHA.
*
         DO 50 J = 1, MIN( M, N )
            DO 40 I = J + 1, M
               A( I, J ) = ALPHA
   40       CONTINUE
   50    CONTINUE
         DO 60 I = 1, MIN( N, M )
            A( I, I ) = BETA
   60    CONTINUE
*
      ELSE
*
*        Set the array to BETA on the diagonal and ALPHA on the
*        offdiagonal.
*
         DO 80 J = 1, N
            DO 70 I = 1, M
               A( I, J ) = ALPHA
   70       CONTINUE
   80    CONTINUE
         DO 90 I = 1, MIN( M, N )
            A( I, I ) = BETA
   90    CONTINUE
      END IF
*
      RETURN
*
*     End of ZLASET
*
      END
