Abdelrahman Said
117 lines
2.9 KiB
C
117 lines
2.9 KiB
C
/* -- translated by f2c (version 20240504).
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You must link the resulting object file with libf2c:
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on Microsoft Windows system, link with libf2c.lib;
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on Linux or Unix systems, link with .../path/to/libf2c.a -lm
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or, if you install libf2c.a in a standard place, with -lf2c -lm
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-- in that order, at the end of the command line, as in
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cc *.o -lf2c -lm
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Source for libf2c is in /netlib/f2c/libf2c.zip, e.g.,
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http://www.netlib.org/f2c/libf2c.zip
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*/
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#include "f2c.h"
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/* > \brief \b DLAPY2 returns sqrt(x2+y2).
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=========== DOCUMENTATION ===========
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Online html documentation available at
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http://www.netlib.org/lapack/explore-html/
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> \htmlonly
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> Download DLAPY2 + dependencies
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> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dlapy2.
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f">
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> [TGZ]</a>
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> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/dlapy2.
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f">
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> [ZIP]</a>
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> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dlapy2.
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f">
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> [TXT]</a>
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> \endhtmlonly
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Definition:
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===========
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DOUBLE PRECISION FUNCTION DLAPY2( X, Y )
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DOUBLE PRECISION X, Y
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> \par Purpose:
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=============
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>
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> \verbatim
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>
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> DLAPY2 returns sqrt(x**2+y**2), taking care not to cause unnecessary
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> overflow.
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> \endverbatim
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Arguments:
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==========
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> \param[in] X
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> \verbatim
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> X is DOUBLE PRECISION
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> \endverbatim
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>
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> \param[in] Y
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> \verbatim
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> Y is DOUBLE PRECISION
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> X and Y specify the values x and y.
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> \endverbatim
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Authors:
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========
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> \author Univ. of Tennessee
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> \author Univ. of California Berkeley
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> \author Univ. of Colorado Denver
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> \author NAG Ltd.
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> \date September 2012
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> \ingroup auxOTHERauxiliary
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===================================================================== */
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doublereal igraphdlapy2_(doublereal *x, doublereal *y)
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{
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/* System generated locals */
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doublereal ret_val, d__1;
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/* Builtin functions */
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double sqrt(doublereal);
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/* Local variables */
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doublereal w, z__, xabs, yabs;
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/* -- LAPACK auxiliary routine (version 3.4.2) --
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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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September 2012
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===================================================================== */
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xabs = abs(*x);
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yabs = abs(*y);
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w = max(xabs,yabs);
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z__ = min(xabs,yabs);
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if (z__ == 0.) {
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ret_val = w;
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} else {
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/* Computing 2nd power */
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d__1 = z__ / w;
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ret_val = w * sqrt(d__1 * d__1 + 1.);
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}
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return ret_val;
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/* End of DLAPY2 */
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} /* igraphdlapy2_ */
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