fix scripts failing with no processing mode set

fixes #499

bin/BarTracker

@@ -79,6 +79,7 @@ def main():
         # signal processor
         signal_processor = SignalProcessor(**vars(args))
         # beats processor
+        load_beats_processor = None
         if hasattr(args, 'infile'):
             # single mode: read the beats from STDIN
             load_beats_processor = LoadBeatsProcessor(**vars(args))

bin/evaluate

@@ -52,6 +52,11 @@ def main():
     # parse the args
     args = p.parse_args()
 
+    # print usage if no evaluation mode was set
+    if not getattr(args, 'eval', False):
+        p.print_usage()
+        exit(0)
+
     # print the arguments
     if args.verbose >= 2:
         print(args)

madmom/processors.py

@@ -947,6 +947,14 @@ def io_arguments(parser, output_suffix='.txt', pickle=True, online=False):
     # add general options
     parser.add_argument('-v', dest='verbose', action='count',
                         help='increase verbosity level')
+
+    # print usage if no processing mode is set
+    def print_usage(*args, **kwargs):
+        parser.print_usage()
+        exit(0)
+
+    parser.set_defaults(func=print_usage)
+
     # add subparsers
     sub_parsers = parser.add_subparsers(title='processing options')