diff options
Diffstat (limited to 'src/rand.c')
-rw-r--r-- | src/rand.c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/src/rand.c b/src/rand.c new file mode 100644 index 0000000..1a6a3d4 --- /dev/null +++ b/src/rand.c @@ -0,0 +1,20 @@ + +#include "fracture.h" + +unsigned long int rand_seed() { + FILE *f = fopen("/dev/urandom", "r"); + unsigned long int seed; + fread(&seed, sizeof(unsigned long int), 1, f); + fclose(f); + return seed; +} + +double rand_dist_pow(const gsl_rng *r, double beta) { + double x = 0; + + // underflow means that for very small beta x is sometimes identically zero, + // which causes problems + while ((x = exp(log(gsl_rng_uniform_pos(r)) / beta)) == 0.0); + + return x; +} |