Adds only calculation mode.

plot_gps.py

@@ -55,7 +55,7 @@ if __name__ == "__main__":
     parser.add_argument("--no_legend", action="store_false", default=True, help="Do not show legend.")
     parser.add_argument("--save", default=None, help="Location to save pdf file.")
     parser.add_argument("--time_offset", default=None, type=int, help="Minutes added to GPS datetime.")
-    parser.add_argument("--no_plot", default=False, type=bool, help="Only calculations without plotting.")
+    parser.add_argument("--no_plot", default=False, action="store_true", help="Only calculations without plotting.")
 
     parser.add_argument(
         "--show_providerinfo",