import math
from pi_tests import test
def gaussLegendre():
pi_old = 1.0
pi_new = 2.0
a0 = 1.0
b0 = 1.0/math.sqrt(2)
t0 = .25
p0 = 1.0
while (pi_new - pi_old != 0):
pi_old = pi_new
a1 = (a0 + b0)/2.0
b1 = math.sqrt(a0 * b0)
t1 = t0 - p0 * (a0 - a1)**2
p1 = 2*p0
a0 = a1
b0 = b1
t0 = t1
p0 = p1
pi_new = (a0 + b0)**2 / (4 * t0)
# print pi_new
return pi_new
if __name__ == "__main__":
test(gaussLegendre)
