A way of checking if a string contains a number

[Larry Bates]

Hamish wrote:
> Hey
> 
> I'm new to python, but I have used a fair bit of C and Perl
> 
> I found Perls regex's to be very easy to use however I don't find
> Pythons regexes as good.
> 
> All I am trying to do is detect if there is a number in a string.
> 
> I am reading the string from an excel spread sheet using the xlrd
> module
> 
> then I would like to test if this string has a number in it
> 
> ie.
> import xlrd
> import re
> 
> doesHaveNumber = re.compile('[0-9]')
> string1 = ABC 11
> 
> regularExpressionCheck = doesHaveNumber.search(string1)
> 
> This will get the right result but then I would like to use the result
> in an IF statement and have not had much luck with it.
> 
> if regularExpressionCheck != "None"
>       print "Something"
> 
> the result is that it prints every line from the spreadsheet to output
> but I only want the lines from the spreadsheet to output.
> 
> Is there a way I can drop the regular expression module and just use
> built in string processing?
> 
> Why si the output from checks in teh re module either "None" or some
> crazy memory address? Couldn't it be just true or false?
> 
> 
> 
> 
> 
> 
> 
regularExpressionCheck won't ever contain the characters "None".  The result
if doesHaveNumber.search(string1) is a match object not a string.  IMHO regular 
expressions are overkill for the task you describe.  You may be better served to 
just try to convert it to whatever number you want.

try:
     value=int(string1)

except ValueError:
     # do whatever you want for non integers here

else:
     # do whatever you want for integers here

Or use string methods:

if string1.isdigit():
     print "digits found"
else:
     print "alphas found"

-Larry