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/* ------------------------------------------------------------- */
/* File: example2_str.c */
/* ------------------------------------------------------------- */
/* String API. */
/* ------------------------------------------------------------- */
/* Include UNURAN header file. */
#include <unuran.h>
/* ------------------------------------------------------------- */
/* In this example we use a generic distribution object */
/* and sample from this distribution. */
/* */
/* The PDF of our distribution is given by */
/* */
/* / 1 - x*x if |x| <= 1 */
/* f(x) = < */
/* \ 0 otherwise */
/* */
/* We use method TDR (Transformed Density Rejection) which */
/* required a PDF and the derivative of the PDF. */
/* ------------------------------------------------------------- */
int main(void)
{
int i; /* loop variable */
double x; /* will hold the random number */
/* Declare UNURAN generator object. */
UNUR_GEN *gen; /* generator object */
/* Create the generator object. */
/* Use a generic continuous distribution. */
/* Choose a method: TDR. */
gen = unur_str2gen(
"distr = cont; pdf=\"1-x*x\"; domain=(-1,1) & method=tdr");
/* 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);
}
/* Now you can use the generator object `gen' to sample from */
/* the distribution. Eg.: */
for (i=0; i<10; i++) {
x = unur_sample_cont(gen);
printf("%f\n",x);
}
/* 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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