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    1:       SUBROUTINE ZLASET( UPLO, M, N, ALPHA, BETA, A, LDA )
    2: *
    3: *  -- LAPACK auxiliary routine (version 3.2) --
    4: *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
    5: *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
    6: *     November 2006
    7: *
    8: *     .. Scalar Arguments ..
    9:       CHARACTER          UPLO
   10:       INTEGER            LDA, M, N
   11:       COMPLEX*16         ALPHA, BETA
   12: *     ..
   13: *     .. Array Arguments ..
   14:       COMPLEX*16         A( LDA, * )
   15: *     ..
   16: *
   17: *  Purpose
   18: *  =======
   19: *
   20: *  ZLASET initializes a 2-D array A to BETA on the diagonal and
   21: *  ALPHA on the offdiagonals.
   22: *
   23: *  Arguments
   24: *  =========
   25: *
   26: *  UPLO    (input) CHARACTER*1
   27: *          Specifies the part of the matrix A to be set.
   28: *          = 'U':      Upper triangular part is set. The lower triangle
   29: *                      is unchanged.
   30: *          = 'L':      Lower triangular part is set. The upper triangle
   31: *                      is unchanged.
   32: *          Otherwise:  All of the matrix A is set.
   33: *
   34: *  M       (input) INTEGER
   35: *          On entry, M specifies the number of rows of A.
   36: *
   37: *  N       (input) INTEGER
   38: *          On entry, N specifies the number of columns of A.
   39: *
   40: *  ALPHA   (input) COMPLEX*16
   41: *          All the offdiagonal array elements are set to ALPHA.
   42: *
   43: *  BETA    (input) COMPLEX*16
   44: *          All the diagonal array elements are set to BETA.
   45: *
   46: *  A       (input/output) COMPLEX*16 array, dimension (LDA,N)
   47: *          On entry, the m by n matrix A.
   48: *          On exit, A(i,j) = ALPHA, 1 <= i <= m, 1 <= j <= n, i.ne.j;
   49: *                   A(i,i) = BETA , 1 <= i <= min(m,n)
   50: *
   51: *  LDA     (input) INTEGER
   52: *          The leading dimension of the array A.  LDA >= max(1,M).
   53: *
   54: *  =====================================================================
   55: *
   56: *     .. Local Scalars ..
   57:       INTEGER            I, J
   58: *     ..
   59: *     .. External Functions ..
   60:       LOGICAL            LSAME
   61:       EXTERNAL           LSAME
   62: *     ..
   63: *     .. Intrinsic Functions ..
   64:       INTRINSIC          MIN
   65: *     ..
   66: *     .. Executable Statements ..
   67: *
   68:       IF( LSAME( UPLO, 'U' ) ) THEN
   69: *
   70: *        Set the diagonal to BETA and the strictly upper triangular
   71: *        part of the array to ALPHA.
   72: *
   73:          DO 20 J = 2, N
   74:             DO 10 I = 1, MIN( J-1, M )
   75:                A( I, J ) = ALPHA
   76:    10       CONTINUE
   77:    20    CONTINUE
   78:          DO 30 I = 1, MIN( N, M )
   79:             A( I, I ) = BETA
   80:    30    CONTINUE
   81: *
   82:       ELSE IF( LSAME( UPLO, 'L' ) ) THEN
   83: *
   84: *        Set the diagonal to BETA and the strictly lower triangular
   85: *        part of the array to ALPHA.
   86: *
   87:          DO 50 J = 1, MIN( M, N )
   88:             DO 40 I = J + 1, M
   89:                A( I, J ) = ALPHA
   90:    40       CONTINUE
   91:    50    CONTINUE
   92:          DO 60 I = 1, MIN( N, M )
   93:             A( I, I ) = BETA
   94:    60    CONTINUE
   95: *
   96:       ELSE
   97: *
   98: *        Set the array to BETA on the diagonal and ALPHA on the
   99: *        offdiagonal.
  100: *
  101:          DO 80 J = 1, N
  102:             DO 70 I = 1, M
  103:                A( I, J ) = ALPHA
  104:    70       CONTINUE
  105:    80    CONTINUE
  106:          DO 90 I = 1, MIN( M, N )
  107:             A( I, I ) = BETA
  108:    90    CONTINUE
  109:       END IF
  110: *
  111:       RETURN
  112: *
  113: *     End of ZLASET
  114: *
  115:       END