| /* multiroots/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_multiroots.h> |
| |
| int |
| gsl_multiroot_test_delta (const gsl_vector * dx, const gsl_vector * x, |
| double epsabs, double epsrel) |
| { |
| size_t i; |
| int ok = 1; |
| const size_t n = x->size ; |
| |
| if (epsrel < 0.0) |
| { |
| GSL_ERROR ("relative tolerance is negative", GSL_EBADTOL); |
| } |
| |
| for (i = 0 ; i < n ; i++) |
| { |
| double xi = gsl_vector_get(x,i); |
| double dxi = gsl_vector_get(dx,i); |
| double tolerance = epsabs + epsrel * fabs(xi) ; |
| |
| if (fabs(dxi) < tolerance) |
| { |
| ok = 1; |
| } |
| else |
| { |
| ok = 0; |
| break; |
| } |
| } |
| |
| if (ok) |
| return GSL_SUCCESS ; |
| |
| return GSL_CONTINUE; |
| } |
| |
| int |
| gsl_multiroot_test_residual (const gsl_vector * f, double epsabs) |
| { |
| size_t i; |
| |
| double residual = 0; |
| |
| const size_t n = f->size; |
| |
| if (epsabs < 0.0) |
| { |
| GSL_ERROR ("absolute tolerance is negative", GSL_EBADTOL); |
| } |
| |
| for (i = 0 ; i < n ; i++) |
| { |
| double fi = gsl_vector_get(f, i); |
| |
| residual += fabs(fi); |
| } |
| |
| |
| if (residual < epsabs) |
| { |
| return GSL_SUCCESS; |
| } |
| |
| return GSL_CONTINUE ; |
| } |
| |