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#include <stdio.h>
#include <time.h>
#include <stc/crandom.h>
#include <stc/cstr.h>
int main()
{
enum {R = 30};
const size_t N = 1000000000;
clock_t difference, before;
uint64_t sum = 0;
uint64_t seed = time(NULL);
crand_rng32_t pcg = crand_rng32_init(seed);
uint32_t range = crand_i32(&pcg) & ((1u << 28) - 1);
crand_uniform_i32_t dist0 = crand_uniform_i32_init(0, range);
printf("32 uniform: %u\n", dist0.range);
double fsum = 0;
before = clock();
c_forrange (N) {
fsum += (double) crand_uniform_i32(&pcg, &dist0) / dist0.range;
}
difference = clock() - before;
printf("%zu %f: %f secs\n", N, fsum / N, (float) difference / CLOCKS_PER_SEC);
pcg = crand_rng32_init(seed);
dist0 = crand_uniform_i32_init(0, range);
puts("32 unbiased");
fsum = 0;
before = clock();
c_forrange (N) {
fsum += (double) crand_unbiased_i32(&pcg, &dist0) / dist0.range;
}
difference = clock() - before;
printf("%zu %f: %f secs\n", N, fsum / N, (float) difference / CLOCKS_PER_SEC);
puts("64 uniform");
crand_rng64_t stc = crand_rng64_init(seed);
crand_uniform_i64_t dist1 = crand_uniform_i64_init(0, N);
sum = 0;
before = clock();
c_forrange (N) {
sum += crand_uniform_i64(&stc, &dist1);
}
difference = clock() - before;
printf("%zu %f: %f secs\n", N, (double) sum / N, (float) difference / CLOCKS_PER_SEC);
puts("normal distribution");
crand_normal_f64_t dist2 = crand_normal_f64_init(R / 2.0, R / 6.0);
size_t N2 = 10000000;
int hist[R] = {0};
sum = 0;
c_forrange (N2) {
int n = (int) (crand_normal_f64(&stc, &dist2) + 0.5);
sum += n;
if (n >= 0 && n < R) ++hist[n];
}
cstr_t bar = cstr_init();
c_forrange (i, int, R) {
cstr_take(&bar, cstr_with_size(hist[i] * 25ull * R / N2, '*'));
printf("%2d %s\n", i, bar.str);
}
cstr_del(&bar);
}
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