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      SUBROUTINE DLASET( UPLO, M, N, ALPHA, BETA, A, LDA )
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*
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*  -- LAPACK auxiliary routine (version 3.2) --
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*  -- LAPACK is a software package provided by Univ. of Tennessee,    --
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*  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
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*     November 2006
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*
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*     .. Scalar Arguments ..
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      CHARACTER          UPLO
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      INTEGER            LDA, M, N
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      DOUBLE PRECISION   ALPHA, BETA
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*     ..
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*     .. Array Arguments ..
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      DOUBLE PRECISION   A( LDA, * )
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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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*  DLASET initializes an m-by-n matrix A to BETA on the diagonal and
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*  ALPHA on the offdiagonals.
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*
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*  Arguments
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*  =========
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*
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*  UPLO    (input) CHARACTER*1
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*          Specifies the part of the matrix A to be set.
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*          = 'U':      Upper triangular part is set; the strictly lower
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*                      triangular part of A is not changed.
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*          = 'L':      Lower triangular part is set; the strictly upper
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*                      triangular part of A is not changed.
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*          Otherwise:  All of the matrix A is set.
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*
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*  M       (input) INTEGER
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*          The number of rows of the matrix A.  M >= 0.
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*
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*  N       (input) INTEGER
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*          The number of columns of the matrix A.  N >= 0.
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*
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*  ALPHA   (input) DOUBLE PRECISION
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*          The constant to which the offdiagonal elements are to be set.
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*
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*  BETA    (input) DOUBLE PRECISION
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*          The constant to which the diagonal elements are to be set.
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*
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*  A       (input/output) DOUBLE PRECISION array, dimension (LDA,N)
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*          On exit, the leading m-by-n submatrix of A is set as follows:
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*
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*          if UPLO = 'U', A(i,j) = ALPHA, 1<=i<=j-1, 1<=j<=n,
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*          if UPLO = 'L', A(i,j) = ALPHA, j+1<=i<=m, 1<=j<=n,
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*          otherwise,     A(i,j) = ALPHA, 1<=i<=m, 1<=j<=n, i.ne.j,
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*
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*          and, for all UPLO, A(i,i) = BETA, 1<=i<=min(m,n).
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*
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*  LDA     (input) INTEGER
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*          The leading dimension of the array A.  LDA >= max(1,M).
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*
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* =====================================================================
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*
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*     .. Local Scalars ..
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      INTEGER            I, J
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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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*     .. Intrinsic Functions ..
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      INTRINSIC          MIN
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*     ..
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*     .. Executable Statements ..
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*
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      IF( LSAME( UPLO, 'U' ) ) THEN
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*
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*        Set the strictly upper triangular or trapezoidal part of the
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*        array to ALPHA.
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*
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         DO 20 J = 2, N
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            DO 10 I = 1, MIN( J-1, M )
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               A( I, J ) = ALPHA
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   10       CONTINUE
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   20    CONTINUE
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*
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      ELSE IF( LSAME( UPLO, 'L' ) ) THEN
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*
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*        Set the strictly lower triangular or trapezoidal part of the
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*        array to ALPHA.
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*
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         DO 40 J = 1, MIN( M, N )
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            DO 30 I = J + 1, M
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               A( I, J ) = ALPHA
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   30       CONTINUE
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   40    CONTINUE
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*
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      ELSE
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*
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*        Set the leading m-by-n submatrix to ALPHA.
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*
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         DO 60 J = 1, N
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            DO 50 I = 1, M
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               A( I, J ) = ALPHA
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   50       CONTINUE
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   60    CONTINUE
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      END IF
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*
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*     Set the first min(M,N) diagonal elements to BETA.
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*
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      DO 70 I = 1, MIN( M, N )
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         A( I, I ) = BETA
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   70 CONTINUE
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*
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      RETURN
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*
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*     End of DLASET
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*
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      END