| /* min/convergence.c |
| * |
| * Copyright (C) 1996, 1997, 1998, 1999, 2000 Brian Gough |
| * |
| * 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, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. |
| */ |
| |
| #include <config.h> |
| #include <gsl/gsl_math.h> |
| #include <gsl/gsl_errno.h> |
| #include <gsl/gsl_min.h> |
| |
| int |
| gsl_min_test_interval (double x_lower, double x_upper, double epsabs, double epsrel) |
| { |
| const double lower = x_lower; |
| const double upper = x_upper; |
| |
| const double abs_lower = fabs(lower) ; |
| const double abs_upper = fabs(upper) ; |
| |
| double min_abs, tolerance; |
| |
| if (epsrel < 0.0) |
| GSL_ERROR ("relative tolerance is negative", GSL_EBADTOL); |
| |
| if (epsabs < 0.0) |
| GSL_ERROR ("absolute tolerance is negative", GSL_EBADTOL); |
| |
| if (lower > upper) |
| GSL_ERROR ("lower bound larger than upper_bound", GSL_EINVAL); |
| |
| if ((lower > 0 && upper > 0) || (lower < 0 && upper < 0)) |
| { |
| min_abs = GSL_MIN_DBL(abs_lower, abs_upper) ; |
| } |
| else |
| { |
| min_abs = 0; |
| } |
| |
| tolerance = epsabs + epsrel * min_abs ; |
| |
| if (fabs(upper - lower) < tolerance) |
| return GSL_SUCCESS; |
| |
| return GSL_CONTINUE ; |
| } |
| |