try surrounding your sum argument in brackets: sum([phi(x // ps[i+1], i) for i in range(a)])
instead of: sum(phi(x // ps[i+1], i) for i in range(a)) On Nov 18, 5:23 pm, Michael Press <[EMAIL PROTECTED]> wrote: > I have not written python codes nor run any. I saw this > code posted and decided to try it. It fails. I read the > tutorial and the entry for the built in function sum, > but still do not see the problem. The code was cut and > paste. Please help. Thanks. > > _________________________BEGIN_CODE_________________________ > #!/usr/bin/python > > ps = [none, 2,3,5,7,11,13,17,19,23,29] > > def phi(x, a): > return x - sum(phi(x // ps[i+1], i) for i in range(a)) > > def pi(n): > from math import sqrt > if n <= 1: > return 0 > a = pi(int(sqrt(n))) > return phi(n, a) + a - 1 > __________________________END_CODE__________________________ > > Here is the result of running it: > > File "/Users/mdp/source/prime_counter_python", line 6 > return x - sum(phi(x // ps[i+1], i) for i in range(a)) > ^ > SyntaxError: invalid syntax > > Here are some lines from python -v: > > Python 2.3 (#1, Sep 13 2003, 00:49:11) > [GCC 3.3 20030304 (Apple Computer, Inc. build 1495)] on darwin > Type "help", "copyright", "credits" or "license" for more information > > -- > Michael Press -- http://mail.python.org/mailman/listinfo/python-list
