Memo to use Python: optparse

Reference:

• http://docs.python.org/library/optparse.html
  
• http://www.python.org/doc/2.5.2/lib/module-optparse.html
  

A good tutorial: http://blog.doughellmann.com/2007/08/pymotw-optparse.html

This is an simple example of optparse, a command line parser in Python.

You can copy it and modify it free.

# Loading command line parser, this is better.

import optparse

# Loading basic libraries

import sys

# This is command line parser setting

usage = "Usage: #pprog [options] arg"

parser = optparse.OptionParser(usage)

# You can add the options in the following format

parser.add_option('-o', '--output', 

                  dest="output_filename", 

                  default="default.out",

  help="Given a output",

                  )

parser.add_option('-i', '--input',

                  dest="input_filename",

                  default="default.in",

  help="Given a input",

                  )

parser.add_option('-v', '--version',

                  dest="version",

                  default=1.0,

                  type="float",

  help="Show the version",

                  )

parser.add_option('-d', '--debug',

                  dest="debug",

                  default=False,

                  action="store_true",

  help="Debug mode, all information will be printed in debug.out",

                  )  

parser.add_option('-g', '--graphic',

                  dest="graphic",

                  default=False,

                  action="store_true",

  help="Graphic mode, print the result in graphic",

                  )   

options, remainder = parser.parse_args()

# This is main function

# if no option print help()

if len(sys.argv) == 1:

parser.print_help()

# if we have more than one option, print option table

if len(sys.argv) > 1:

print 'ARGV      :', sys.argv[1:]

print 'VERSION   :', options.version

print 'INPUT     :', options.input_filename

print 'OUTPUT    :', options.output_filename

print 'DEBUG     :', options.debug

print 'GRAPHIC   :', options.graphic

# Then you can use the options to setting your variables and parameters

Reminder #1

if you use the function, "defualt", on your options.debug, you won't get the options.debug == None, because options.debug will have a defualt.

So you are impossible to use if statements to get options.debug == None.

If you need the if statements to check options.debug == None, you have to remove the function, options.default.