sim.py displays help if run with no arguments

1 files changed, 8 insertions, 7 deletions

diff --git a/sim.py b/sim.py
index c52a071..3336f4d 100755
--- a/sim.py
+++ b/sim.py
@@ -1,6 +1,5 @@
 #!/usr/bin/env python
 import sys
-import optparse
 import time
 import os
 import numpy as np
@@ -80,6 +79,7 @@ class Simulation(object):
 
             if run_daq:
                 ev.hits = self.gpu_worker.get_hits()        
+                ev.channels = ev.hits
 
             yield ev
 
@@ -90,7 +90,9 @@ class Simulation(object):
 
 @profile_if_possible
 def main():
-    parser = optparse.OptionParser('%prog')
+    import optparse
+
+    parser = optparse.OptionParser('%prog filename')
     parser.add_option('-b', type='int', dest='nbits', default=11)
     parser.add_option('-j', type='int', dest='device', default=None)
     parser.add_option('-s', type='int', dest='seed', default=None,
@@ -111,15 +113,14 @@ def main():
                       help='Save final photon vertices to disk')
 
     options, args = parser.parse_args()
-    if len(args) != 1:
-        print 'Must specify output filename!'
-        sys.exit(1)
+
+    if len(args) < 1:
+        sys.exit(parser.format_help())
     else:
         output_filename = args[0]
 
     if options.nevents <= 0:
-        print '--nevents must be greater than 0!'
-        sys.exit(1)
+        sys.exit('--nevents must be greater than 0!')
 
     position = np.array(eval(options.pos), dtype=float)
     direction = np.array(eval(options.dir), dtype=float)