Pass arguments from cmd to python script

Question

I write my scripts in python and run them with cmd by typing in:

C:\\> python script.py

Some of my scripts contain separate algorithms a

Answer 1

Try using the getopt module. It can handle both short and long command line options and is implemented in a similar way in other languages (C, shell scripting, etc):

import sys, getopt


def main(argv):

    # default algorithm:
    algorithm = 1

    # parse command line options:
    try:
       opts, args = getopt.getopt(argv,"a:",["algorithm="])
    except getopt.GetoptError:
       
       sys.exit(2)

    for opt, arg in opts:
       if opt in ("-a", "--algorithm"):
          # use alternative algorithm:
          algorithm = arg

    print "Using algorithm: ", algorithm

    # Positional command line arguments (i.e. non optional ones) are
    # still available via 'args':
    print "Positional args: ", args

if __name__ == "__main__":
   main(sys.argv[1:])

You can then pass specify a different algorithm by using the -a or --algorithm= options:

python  -a2               # use algorithm 2
python  --algorithm=2    # ditto

See: getopt documentation