How do I restrict the values of the argparse options?
In the below code sau
option should only accept a number of 0
or 1
and bg
should only allow an integer. How can I implement this?
import os
import sys, getopt
import argparse
def main ():
parser = argparse.ArgumentParser(description='Test script')
parser.add_argument('-sau','--set',action='store',dest='set',help='<Required> Set flag',required=True)
parser.add_argument('-bg','--base_g',action='store',dest='base_g',help='<Required> Base g',required=True)
results = parser.parse_args() # collect cmd line args
set = results.set
base_g = results.base_g
if __name__ == '__main__':
main()
You can use the type=
and choices=
arguments of add_argument
. To accept only '0'
and '1'
, you'd do:
parser.add_argument(…, choices={"0", "1"})
And to accept only integer numbers, you'd do:
parser.add_argument(…, type=int)
Note that in choices
, you have to give the options in the type you specified as the type
argument. So to check for integers and allow only 0
and 1
, you'd do:
parser.add_argument(…, type=int, choices={0, 1})
Example:
>>> import argparse
>>> parser = argparse.ArgumentParser()
>>> _ = parser.add_argument("-p", type=int, choices={0, 1})
>>> parser.parse_args(["-p", "0"])
Namespace(p=0)