Parse a string into a list of numbers

gistfile1.py

from itertools import *

def tonumberlist(s):
    rc = []
    def shouldtake(x):
        return str.isdigit(x) or x=='.'
    i = iter(s.replace(' ',''))
    while True:
        try: 
            rc.append(float(''.join(takewhile(shouldtake, i))))
        except ValueError: break
    return rc

s = "12.1, 5; 66.32,123"
print tonumberlist(s)