Update cmd_interface.py

moved the input file argument after the keyword arguments to make the help message consistent with the behaviour of the interface

lammps_logfile/cmd_interface.py

@@ -5,10 +5,10 @@
 
 def get_parser():
     parser = argparse.ArgumentParser(description="Plot contents from lammps log files")
-    parser.add_argument("input_file", type=str, help="Lammps log file containing thermo output from lammps simulation.")
     parser.add_argument("-x", type=str, default="Time", help="Data to plot on the first axis")
     parser.add_argument("-y", type=str, nargs="+", help="Data to plot on the second axis. You can supply several names to get several plot lines in the same figure.")
     parser.add_argument("-a", "--running_average", type=int, default=1, help="Optionally average over this many log entries with a running average. Some thermo properties fluctuate wildly, and often we are interested in te running average of properties like temperature and pressure.")
+    parser.add_argument("input_file", type=str, help="Lammps log file containing thermo output from lammps simulation.")
     return parser
 
 def run():