To parse a string to float, you can use the following:
try: print float('112.15') except ValueError: print 'Cannot parse'
This will give you the output:
112.15
If your string cant be parsed, it'll throw a value error.
You can create a wrapper method that returns booleans for strings you give it. For example,
def isfloat(value): try: float(value) return True except ValueError: return False print (isfloat('112.5'))
OUTPUT
True