Numbers passed as command line arguments in python not interpreted as integers

python argv
Kalyan picture Kalyan · May 25, 2012 · Viewed 83.9k times · Source

I am familiar with C, and have started experimenting in python. My question is regarding the sys.argv command. I've read it is used for a command line interpreter, but when trying to execute a simple program I don't get the results I expect.

Code:

import sys

a = sys.argv[1]
b = sys.argv[2]

print a, b

print a+b

Input:

python mySum.py 100 200

Output: 

100 200
100200

When I add the two arguments they are concatenated instead of the two values being added together. It seems that the values are being taken as strings.

How can I interpret them as numerics?

Answer

Wesley picture Wesley · May 25, 2012

You can convert the arguments to integers using int()

import sys

a = int(sys.argv[1])  b = int(sys.argv[2])

print a, b

print a+b

input: python mySum.py 100 200

output:

100 200
300

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