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Diff for /rpl/lapack/lapack/dlapy3.f between versions 1.3 and 1.18

-version 1.3, 2010/08/06 15:28:41
+version 1.18, 2023/08/07 08:38:55
  Line 1
+ *> \brief \b DLAPY3 returns sqrt(x2+y2+z2).
+ *
+ *  =========== DOCUMENTATION ===========
+ *
+ * Online html documentation available at
+ *            http://www.netlib.org/lapack/explore-html/
+ *
+ *> \htmlonly
+ *> Download DLAPY3 + dependencies
+ *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dlapy3.f">
+ *> [TGZ]</a>
+ *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/dlapy3.f">
+ *> [ZIP]</a>
+ *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dlapy3.f">
+ *> [TXT]</a>
+ *> \endhtmlonly
+ *
+ *  Definition:
+ *  ===========
+ *
+ *       DOUBLE PRECISION FUNCTION DLAPY3( X, Y, Z )
+ *
+ *       .. Scalar Arguments ..
+ *       DOUBLE PRECISION   X, Y, Z
+ *       ..
+ *
+ *
+ *> \par Purpose:
+ *  =============
+ *>
+ *> \verbatim
+ *>
+ *> DLAPY3 returns sqrt(x**2+y**2+z**2), taking care not to cause
+ *> unnecessary overflow and unnecessary underflow.
+ *> \endverbatim
+ *
+ *  Arguments:
+ *  ==========
+ *
+ *> \param[in] X
+ *> \verbatim
+ *>          X is DOUBLE PRECISION
+ *> \endverbatim
+ *>
+ *> \param[in] Y
+ *> \verbatim
+ *>          Y is DOUBLE PRECISION
+ *> \endverbatim
+ *>
+ *> \param[in] Z
+ *> \verbatim
+ *>          Z is DOUBLE PRECISION
+ *>          X, Y and Z specify the values x, y and z.
+ *> \endverbatim
+ *
+ *  Authors:
+ *  ========
+ *
+ *> \author Univ. of Tennessee
+ *> \author Univ. of California Berkeley
+ *> \author Univ. of Colorado Denver
+ *> \author NAG Ltd.
+ *
+ *> \ingroup OTHERauxiliary
+ *
+ *  =====================================================================
        DOUBLE PRECISION FUNCTION DLAPY3( X, Y, Z )
  *
- *  -- LAPACK auxiliary routine (version 3.2) --
+ *  -- LAPACK auxiliary routine --
  *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
  *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
- *     November 2006
  *
  *     .. Scalar Arguments ..
        DOUBLE PRECISION   X, Y, Z
  *     ..
  *
- *  Purpose
- *  =======
- *
- *  DLAPY3 returns sqrt(x**2+y**2+z**2), taking care not to cause
- *  unnecessary overflow.
- *
- *  Arguments
- *  =========
- *
- *  X       (input) DOUBLE PRECISION
- *  Y       (input) DOUBLE PRECISION
- *  Z       (input) DOUBLE PRECISION
- *          X, Y and Z specify the values x, y and z.
- *
  *  =====================================================================
  *
  *     .. Parameters ..
- Line 30
+ Line 81
        PARAMETER          ( ZERO = 0.0D0 )
  *     ..
  *     .. Local Scalars ..
-       DOUBLE PRECISION   W, XABS, YABS, ZABS
+       DOUBLE PRECISION   W, XABS, YABS, ZABS, HUGEVAL
+ *     ..
+ *     .. External Subroutines ..
+       DOUBLE PRECISION   DLAMCH
  *     ..
  *     .. Intrinsic Functions ..
        INTRINSIC          ABS, MAX, SQRT
  *     ..
  *     .. Executable Statements ..
  *
+       HUGEVAL = DLAMCH( 'Overflow' )
        XABS = ABS( X )
        YABS = ABS( Y )
        ZABS = ABS( Z )
        W = MAX( XABS, YABS, ZABS )
-       IF( W.EQ.ZERO ) THEN
+       IF( W.EQ.ZERO .OR. W.GT.HUGEVAL ) THEN
  *     W can be zero for max(0,nan,0)
  *     adding all three entries together will make sure
  *     NaN will not disappear.

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