1000 digits of pi in Python

Question

I have been thinking about this issue and I can\'t figure it out. Perhaps you can assist me. The problem is my code isn\'t working to output 1000 digits of pi in the Python

Answer 1

From Fabrice Bellard site: Pi Computation algorithm. Sorry for such a straightforward implementation. 1000 is fast enough (0.1s for me), but 10000 isn't such fast - 71s :-(

import time
from decimal import Decimal, getcontext

def compute(n):
    getcontext().prec = n
    res = Decimal(0)
    for i in range(n):
        a = Decimal(1)/(16**i)
        b = Decimal(4)/(8*i+1)
        c = Decimal(2)/(8*i+4)
        d = Decimal(1)/(8*i+5)
        e = Decimal(1)/(8*i+6)
        r = a*(b-c-d-e)
        res += r
    return res

if __name__ == "__main__":
    t1 = time.time()
    res = compute(1000)
    dt = time.time()-t1
    print(res)
    print(dt)