why 'lambda' and 'reduce'?

[Anton Vredegoor]

bokr at oz.net (Bengt Richter) wrote:

>I just thought to dig this up and turn it into a generator.
>Something to check against ;-)

<snip pigen.py>

Thanks for posting. After playing a while with it I noticed that the
new itertools for Python23 are nice for this too. The version below
doesn't use "n" and "k" in the generator and computes p and q in a
for-loop. Also d and d1 are dropped for the sake of clarity, at the
cost of computing just one extra a/b. 

Anton

from sys import stdout
from itertools import count,islice,imap

def pq(x): return x*x,2*x+1
    
def pigen():
    a,b,c,d = 12,4,76,24
    for p,q in imap(pq,count(3)):
        while a/b == c/d:
            yield str(a/b)
            a,c = a%b*10, c%d*10
        a,b,c,d = c,d,p*a+q*c,p*b+q*d

def test():
    ndigits = 60
    map(stdout.write,islice(pigen(),ndigits))
    print

if __name__=='__main__':
    test()