silly me, forgot to mention build a set from digits + '.' and use that for testing.
Cheers, PN 2009/2/16 Python Nutter <pythonnut...@gmail.com>: > Type casting seems to be the wrong way to go about this. > > teststring = '15719' > teststring.isdigit() > returns True > > That takes care of integers. > > from string import digits > digits > '0123456789' > > now you have all the digits and you can do set testing in your logic > to see if the teststring has anything in digits > > A dumb way to test is alphanumeric > > teststring2 = '105.22' > teststring2.isalnum() > returns True > > now you can go on from there and test to further to eliminate > 'abcd385laf8' which on alnum() also returns true. > > Have fun, > Cheers, > PN > > > 2009/2/16 <pyt...@bdurham.com>: >> What's the Pythonic way to determine if a string is a number? By >> number I mean a valid integer or float. >> >> I searched the string and cMath libraries for a similar function >> without success. I can think of at least 3 or 4 ways to build my >> own function. >> >> Here's what I came up with as a proof-of-concept. Are there >> 'better' ways to perform this type of test? >> >> Thanks, >> Malcolm >> >> <code> >> def isnumber( input ): >> try: >> if '.' in input: >> num = float( input ) >> else: >> num = int( input ) >> return True >> >> except ValueError: >> return False >> >> if __name__ == '__main__': >> tests = """ >> 12 >> -12 >> -12.34 >> .0 >> . >> 1 2 3 >> 1 . 2 >> just text >> """ >> >> for test in tests.split( '\n' ): >> print 'test (%0s), isnumber: %1s' % \ >> ( test.strip(), isnumber( test ) ) >> >> </code> >> -- >> http://mail.python.org/mailman/listinfo/python-list >> > -- http://mail.python.org/mailman/listinfo/python-list
