Bala subramanian wrote:
> I use the following way to check for the input parameters. I would > like to know if there is a any better way to show or describe the > script usage. So when the user just runs it without any input params., > the program shd not execute but just shows the documentation. > > from sys import argv > if not argv[1:]: > print 'Program usage: python script file-list1 file-list2' > print 'file list should contain the names of the atom list' > -------- > -------- I may look like a lot of overhead at first, but in the long run it will pay off if you use argparse: $ cat argparse_demo.py def main(): import argparse parser = argparse.ArgumentParser( description="what the script is supposed to do") parser.add_argument( "file_list1", metavar="file-list1", help="your help text for file-list1") parser.add_argument( "file_list2", metavar="file-list2", help="your help text for file-list2") args = parser.parse_args() print "Do something with {!r} and {!r}".format( args.file_list1, args.file_list2) if __name__ == "__main__": main() $ python argparse_demo.py usage: argparse_demo.py [-h] file-list1 file-list2 argparse_demo.py: error: too few arguments $ python argparse_demo.py -h usage: argparse_demo.py [-h] file-list1 file-list2 what the script is supposed to do positional arguments: file-list1 your help text for file-list1 file-list2 your help text for file-list2 optional arguments: -h, --help show this help message and exit $ python argparse_demo.py alpha.txt beta.txt Do something with 'alpha.txt' and 'beta.txt' For more see the documentation at http://docs.python.org/howto/argparse.html#id1 _______________________________________________ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor