3 * Copyright (C) 1996, 1997, 1998, 1999, 2000, 2007 Gerard Jungman, Brian Gough, Patrick Alken
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 3 of the License, or (at
8 * your option) any later version.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
22 #include <gsl/gsl_math.h>
24 double gsl_hypot (const double x, const double y);
25 double gsl_hypot3 (const double x, const double y, const double z);
27 double gsl_hypot (const double x, const double y)
29 double xabs = fabs(x) ;
30 double yabs = fabs(y) ;
47 double u = min / max ;
48 return max * sqrt (1 + u * u) ;
53 gsl_hypot3(const double x, const double y, const double z)
55 double xabs = fabs(x);
56 double yabs = fabs(y);
57 double zabs = fabs(z);
58 double w = GSL_MAX(xabs, GSL_MAX(yabs, zabs));
66 double r = w * sqrt((xabs / w) * (xabs / w) +
67 (yabs / w) * (yabs / w) +
68 (zabs / w) * (zabs / w));