Verifying type in input

Posted on 2004-10-13
Last Modified: 2010-04-16
I would like to be able to verify the type of input from an input statement, but I can't seem to be able to figure it out.  For example:

num=raw_input("Enter a number: ")

I would like to then verify that num is an int.

I am sure that it is a bit more easy than in java, and that is probably my problem...I am looking to far into it and can't see the forest through the trees.

Thanks for your help,
Question by:bnblazer
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LVL 11

Expert Comment

ID: 12305582
num = None
while not num:
        num = int( raw_input( "Enter a number: " ) )
        print 'num is definitely an integer number'
        num = None

LVL 11

Accepted Solution

cjjclifford earned 125 total points
ID: 12305593
basically, cast the result of raw_input() to int() (or float() if you want decimal places), catching exception in the case where the cast fails...

probably better to explicitly catch the correct exception, so other errors are not hidden...

num = None
while not num:
        num = int( raw_input( "Enter a number: " ) )
        print 'num is definitely an integer number'
    except ValueError:
        num = None

Author Comment

ID: 12306921
Thank you, that is exactly what I was looking for.


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