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Patches pour OS/2

    1:       SUBROUTINE DLABAD( SMALL, LARGE )
    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:       DOUBLE PRECISION   LARGE, SMALL
   10: *     ..
   11: *
   12: *  Purpose
   13: *  =======
   14: *
   15: *  DLABAD takes as input the values computed by DLAMCH for underflow and
   16: *  overflow, and returns the square root of each of these values if the
   17: *  log of LARGE is sufficiently large.  This subroutine is intended to
   18: *  identify machines with a large exponent range, such as the Crays, and
   19: *  redefine the underflow and overflow limits to be the square roots of
   20: *  the values computed by DLAMCH.  This subroutine is needed because
   21: *  DLAMCH does not compensate for poor arithmetic in the upper half of
   22: *  the exponent range, as is found on a Cray.
   23: *
   24: *  Arguments
   25: *  =========
   26: *
   27: *  SMALL   (input/output) DOUBLE PRECISION
   28: *          On entry, the underflow threshold as computed by DLAMCH.
   29: *          On exit, if LOG10(LARGE) is sufficiently large, the square
   30: *          root of SMALL, otherwise unchanged.
   31: *
   32: *  LARGE   (input/output) DOUBLE PRECISION
   33: *          On entry, the overflow threshold as computed by DLAMCH.
   34: *          On exit, if LOG10(LARGE) is sufficiently large, the square
   35: *          root of LARGE, otherwise unchanged.
   36: *
   37: *  =====================================================================
   38: *
   39: *     .. Intrinsic Functions ..
   40:       INTRINSIC          LOG10, SQRT
   41: *     ..
   42: *     .. Executable Statements ..
   43: *
   44: *     If it looks like we're on a Cray, take the square root of
   45: *     SMALL and LARGE to avoid overflow and underflow problems.
   46: *
   47:       IF( LOG10( LARGE ).GT.2000.D0 ) THEN
   48:          SMALL = SQRT( SMALL )
   49:          LARGE = SQRT( LARGE )
   50:       END IF
   51: *
   52:       RETURN
   53: *
   54: *     End of DLABAD
   55: *
   56:       END