| /* |
| * Mathlib : A C Library of Special Functions |
| * Copyright (C) 1998 Ross Ihaka |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, a copy is available at |
| * https://www.R-project.org/Licenses/ |
| * |
| * SYNOPSIS |
| * |
| * #include <Rmath.h> |
| * double fsign(double x, double y); |
| * |
| * DESCRIPTION |
| * |
| * This function performs transfer of sign. The result is: |
| * |
| * |x| * signum(y) |
| */ |
| |
| #include "nmath.h" |
| |
| double fsign(double x, double y) |
| { |
| #ifdef IEEE_754 |
| if (ISNAN(x) || ISNAN(y)) |
| return x + y; |
| #endif |
| return ((y >= 0) ? fabs(x) : -fabs(x)); |
| } |