| /* histogram/test2d_resample.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 <stdlib.h> |
| #include <math.h> |
| #include <gsl/gsl_histogram2d.h> |
| #include <gsl/gsl_test.h> |
| #include <gsl/gsl_ieee_utils.h> |
| |
| #include "urand.c" |
| |
| void |
| test2d_resample (void) |
| { |
| size_t i, j; |
| int status = 0; |
| double total = 0; |
| size_t N = 200000; |
| |
| gsl_histogram2d *h; |
| |
| gsl_ieee_env_setup (); |
| |
| h = gsl_histogram2d_calloc_uniform (10, 10, 0.0, 1.0, 0.0, 1.0); |
| |
| for (i = 0; i < 10; i++) |
| { |
| for (j = 0; j < 10; j++) |
| { |
| double w = 10.0 * i + j; |
| total += w; |
| gsl_histogram2d_accumulate (h, 0.1 * i, 0.1 * i, w); |
| } |
| } |
| |
| { |
| gsl_histogram2d_pdf *p = gsl_histogram2d_pdf_alloc (10,10); |
| |
| gsl_histogram2d *hh = gsl_histogram2d_calloc_uniform (20, 20, |
| 0.0, 1.0, |
| 0.0, 1.0); |
| |
| gsl_histogram2d_pdf_init (p, h); |
| |
| for (i = 0; i < N; i++) |
| { |
| double u = urand(); |
| double v = urand(); |
| double x, y; |
| status = gsl_histogram2d_pdf_sample (p, u, v, &x, &y); |
| status = gsl_histogram2d_increment (hh, x, y); |
| } |
| |
| status = 0; |
| for (i = 0; i < 20; i++) |
| { |
| for (j = 0; j < 20; j++) |
| { |
| double z = 4 * total * gsl_histogram2d_get (hh, i, j) / (double) N; |
| size_t k1, k2; |
| double ya; |
| double x, xmax, y, ymax; |
| |
| gsl_histogram2d_get_xrange (hh, i, &x, &xmax); |
| gsl_histogram2d_get_yrange (hh, j, &y, &ymax); |
| |
| gsl_histogram2d_find (h, x, y, &k1, &k2); |
| ya = gsl_histogram2d_get (h, k1, k2); |
| |
| if (ya == 0) |
| { |
| if (z != 0) |
| { |
| status = 1; |
| printf ("(%d,%d): %g vs %g\n", (int)i, (int)j, z, ya); |
| } |
| } |
| else |
| { |
| double err = 1 / sqrt (gsl_histogram2d_get (hh, i, j)); |
| double sigma = fabs ((z - ya) / (ya * err)); |
| if (sigma > 3) |
| { |
| status = 1; |
| printf ("%g vs %g err=%g sigma=%g\n", z, ya, err, sigma); |
| } |
| } |
| } |
| } |
| |
| gsl_histogram2d_pdf_free (p) ; |
| gsl_histogram2d_free (hh) ; |
| |
| gsl_test (status, "gsl_histogram2d_pdf_sample within statistical errors"); |
| } |
| |
| gsl_histogram2d_free (h) ; |
| } |