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- /* histogram/test_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., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
- #include <config.h>
- #include <stdlib.h>
- #include <math.h>
- #include <gsl/gsl_histogram.h>
- #include <gsl/gsl_test.h>
- #include <gsl/gsl_ieee_utils.h>
-
- #include "urand.c"
-
- int
- main (void)
- {
- size_t i;
- int status = 0;
-
- gsl_histogram *h;
-
- gsl_ieee_env_setup ();
-
- h = gsl_histogram_calloc_uniform (10, 0.0, 1.0);
-
- gsl_histogram_increment (h, 0.1);
- gsl_histogram_increment (h, 0.2);
- gsl_histogram_increment (h, 0.2);
- gsl_histogram_increment (h, 0.3);
-
- {
- gsl_histogram_pdf *p = gsl_histogram_pdf_alloc (10);
-
- gsl_histogram *hh = gsl_histogram_calloc_uniform (100, 0.0, 1.0);
-
- gsl_histogram_pdf_init (p, h);
-
- for (i = 0; i < 100000; i++)
- {
- double u = urand();
- double x = gsl_histogram_pdf_sample (p, u);
- gsl_histogram_increment (hh, x);
- }
-
- for (i = 0; i < 100; i++)
- {
- double y = gsl_histogram_get (hh, i) / 2500;
- double x, xmax;
- size_t k;
- double ya;
-
- gsl_histogram_get_range (hh, i, &x, &xmax);
-
- gsl_histogram_find (h, x, &k);
- ya = gsl_histogram_get (h, k);
-
- if (ya == 0)
- {
- if (y != 0)
- {
- printf ("%d: %g vs %g\n", (int) i, y, ya);
- status = 1;
- }
- }
- else
- {
- double err = 1 / sqrt (gsl_histogram_get (hh, i));
- double sigma = fabs ((y - ya) / (ya * err));
- if (sigma > 3)
- {
- status = 1;
- printf ("%g vs %g err=%g sigma=%g\n", y, ya, err, sigma);
- }
- }
- }
-
- gsl_histogram_pdf_free (p) ;
- gsl_histogram_free (hh);
-
- gsl_test (status, "gsl_histogram_pdf_sample within statistical errors");
- }
-
- gsl_histogram_free (h);
-
- exit (gsl_test_summary ());
- }
-