| /* min/test_funcs.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 <gsl/gsl_math.h> |
| #include <gsl/gsl_min.h> |
| |
| #include "test.h" |
| |
| gsl_function create_function (double (*f)(double, void *)) |
| { |
| gsl_function F ; |
| F.function = f ; |
| F.params = 0 ; |
| return F ; |
| } |
| |
| double |
| f_cos (double x, void * p) |
| { |
| p = 0; /* avoid warning about unused parameter */ |
| return cos(x); |
| } |
| |
| /* f(x) = x^4 - 1 */ |
| /* minimum at x = 0 */ |
| |
| double |
| func1 (double x, void * p) |
| { |
| p = 0; /* avoid warning about unused parameter */ |
| return pow (x, 4.0) - 1; |
| } |
| |
| /* f(x) = sqrt(|x|) */ |
| /* minimum at x = 0 */ |
| |
| double |
| func2 (double x, void * p) |
| { |
| p = 0; /* avoid warning about unused parameter */ |
| return sqrt(fabs(x)); |
| } |
| |
| |
| /* f(x) = 1 for x < 1 and -exp(-x) for x >= 1 */ |
| /* minimum at x = 1 */ |
| |
| double |
| func3 (double x, void * p) |
| { |
| p = 0; /* avoid warning about unused parameter */ |
| |
| if (x < 1) |
| return 1 ; |
| else |
| return - exp(-x) ; |
| } |
| |
| /* f(x) = x - 30/(1+1e5*(x-0.8)**2) */ |
| /* minimum near x = 0.8 */ |
| |
| double |
| func4 (double x, void * p) |
| { |
| p = 0; /* avoid warning about unused parameter */ |
| |
| return x - 30.0 / (1.0 + 1e5 * pow(x-0.8, 2.0)); |
| } |
| |