1 files changed, 1 insertions, 1 deletions

diff --git a/bin/rtspin.beta.c b/bin/rtspin.beta.c
index 13fd365..3eafa82 100644
--- a/bin/rtspin.beta.c
+++ b/bin/rtspin.beta.c
@@ -219,7 +219,7 @@ int main(int argc, char** argv)
                                 "exceed the period.");
         }
 
-        duration  = atof(argv[optind + 2]);
+        duration  = atof(argv[optind + 3]);
 
         setup_rng(seed);