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/* ------------------------------------------------------------- */
/* File: example_vemp.c */
/* ------------------------------------------------------------- */
/* Include UNURAN header file. */
#include <unuran.h>
/* ------------------------------------------------------------- */
/* Example how to sample from an empirial continuous */
/* multivariate distribution. */
/* ------------------------------------------------------------- */
int main(void)
{
int i;
/* 4 data points of dimension 2 */
double data[] = { 1. ,1., /* 1st data point */
-1.,1., /* 2nd data point */
1.,-1., /* 3rd data point */
-1.,-1. }; /* 4th data point */
double result[2];
/* Declare the three UNURAN objects. */
UNUR_DISTR *distr; /* distribution object */
UNUR_PAR *par; /* parameter object */
UNUR_GEN *gen; /* generator object */
/* Create a distribution object with dimension 2. */
distr = unur_distr_cvemp_new( 2 );
/* Set empirical sample. */
unur_distr_cvemp_set_data(distr, data, 4);
/* Choose a method: VEMPK. */
par = unur_vempk_new(distr);
/* Use variance correction. */
unur_vempk_set_varcor( par, 1 );
/* Create the generator object. */
gen = unur_init(par);
/* It is important to check if the creation of the generator */
/* object was successful. Otherwise `gen' is the NULL pointer */
/* and would cause a segmentation fault if used for sampling. */
if (gen == NULL) {
fprintf(stderr, "ERROR: cannot create generator object\n");
exit (EXIT_FAILURE);
}
/* It is possible to reuse the distribution object to create */
/* another generator object. If you do not need it any more, */
/* it should be destroyed to free memory. */
unur_distr_free(distr);
/* Now you can use the generator object `gen' to sample from */
/* the distribution. Eg.: */
for (i=0; i<10; i++) {
unur_sample_vec(gen, result);
printf("(%f,%f)\n", result[0], result[1]);
}
/* When you do not need the generator object any more, you */
/* can destroy it. */
unur_free(gen);
exit (EXIT_SUCCESS);
} /* end of main() */
/* ------------------------------------------------------------- */
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