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- *> \brief \b SLAPY2
- *
- * =========== DOCUMENTATION ===========
- *
- * Online html documentation available at
- * http://www.netlib.org/lapack/explore-html/
- *
- *> \htmlonly
- *> Download SLAPY2 + dependencies
- *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/slapy2.f">
- *> [TGZ]</a>
- *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/slapy2.f">
- *> [ZIP]</a>
- *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/slapy2.f">
- *> [TXT]</a>
- *> \endhtmlonly
- *
- * Definition:
- * ===========
- *
- * REAL FUNCTION SLAPY2( X, Y )
- *
- * .. Scalar Arguments ..
- * REAL X, Y
- * ..
- *
- *
- *> \par Purpose:
- * =============
- *>
- *> \verbatim
- *>
- *> SLAPY2 returns sqrt(x**2+y**2), taking care not to cause unnecessary
- *> overflow.
- *> \endverbatim
- *
- * Arguments:
- * ==========
- *
- *> \param[in] X
- *> \verbatim
- *> X is REAL
- *> \endverbatim
- *>
- *> \param[in] Y
- *> \verbatim
- *> Y is REAL
- *> X and Y specify the values x and y.
- *> \endverbatim
- *
- * Authors:
- * ========
- *
- *> \author Univ. of Tennessee
- *> \author Univ. of California Berkeley
- *> \author Univ. of Colorado Denver
- *> \author NAG Ltd.
- *
- *> \date November 2011
- *
- *> \ingroup auxOTHERauxiliary
- *
- * =====================================================================
- REAL FUNCTION SLAPY2( X, Y )
- *
- * -- LAPACK auxiliary routine (version 3.4.0) --
- * -- LAPACK is a software package provided by Univ. of Tennessee, --
- * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
- * November 2011
- *
- * .. Scalar Arguments ..
- REAL X, Y
- * ..
- *
- * =====================================================================
- *
- * .. Parameters ..
- REAL ZERO
- PARAMETER ( ZERO = 0.0E0 )
- REAL ONE
- PARAMETER ( ONE = 1.0E0 )
- * ..
- * .. Local Scalars ..
- REAL W, XABS, YABS, Z
- * ..
- * .. Intrinsic Functions ..
- INTRINSIC ABS, MAX, MIN, SQRT
- * ..
- * .. Executable Statements ..
- *
- XABS = ABS( X )
- YABS = ABS( Y )
- W = MAX( XABS, YABS )
- Z = MIN( XABS, YABS )
- IF( Z.EQ.ZERO ) THEN
- SLAPY2 = W
- ELSE
- SLAPY2 = W*SQRT( ONE+( Z / W )**2 )
- END IF
- RETURN
- *
- * End of SLAPY2
- *
- END
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