Add coin flipping to RTSpin.Betawip-dissipation-jerickso

1 files changed, 13 insertions, 3 deletions

diff --git a/bin/rtspin.beta.c b/bin/rtspin.beta.c
index 4c8a56f..556660e 100644
--- a/bin/rtspin.beta.c
+++ b/bin/rtspin.beta.c
@@ -36,13 +36,16 @@ static int num[NUMS];
 static char* progname;
 
 static gsl_rng *beta_rng;
+static gsl_rng *coin_rng;
 
 static void setup_rng(unsigned long seed)
 {
         beta_rng = gsl_rng_alloc(gsl_rng_taus);
-        if (!beta_rng)
+        coin_rng = gsl_rng_alloc(gsl_rng_taus);
+        if (!beta_rng || !coin_rng)
                 bail_out("Could not initialize RNG");
         gsl_rng_set(beta_rng, seed);
+        gsl_rng_set(coin_rng, seed);
 }
 
 static int loop_once(void)
@@ -122,6 +125,8 @@ enum crit_level str2crit(const char* str)
 
 #define OPTSTR "a:b:d:p:c:wlves:r:i:"
 
+#define COIN_PROB 0.5
+
 int main(int argc, char** argv)
 {
         int ret;
@@ -257,8 +262,12 @@ int main(int argc, char** argv)
         start = wctime();
 
         do {
-                beta_sample = gsl_ran_beta(beta_rng, alpha, beta);
-                exec_time = lvl_c_time * 20.0 * beta_sample * scale;
+                double coin_flip = gsl_rng_uniform(coin_rng);
+                if (coin_flip < COIN_PROB) {
+                        beta_sample = gsl_ran_beta(beta_rng, alpha, beta);
+                        exec_time = lvl_c_time * 20.0 * beta_sample * scale;
+                } else
+                        exec_time = lvl_c_time;
                 /* convert to seconds */
                 exec_time = exec_time * 0.000000001;
         } while(job(exec_time, start + duration));
@@ -268,6 +277,7 @@ int main(int argc, char** argv)
                 bail_out("could not become regular task (huh?)");
 
         gsl_rng_free(beta_rng);
+        gsl_rng_free(coin_rng);
 
         return 0;
 }