rustedbytes-pi 0.1.0

Computes digits of Pi using the Chudnovsky algorithm
Documentation 
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#Note: For extreme calculations, other code can be used to run on a GPU, which is much faster than this.
import decimal

import sys
sys.set_int_max_str_digits(0)

def binary_split(a, b):
    if b == a + 1:
        Pab = -(6*a - 5)*(2*a - 1)*(6*a - 1)
        Qab = 10939058860032000 * a**3
        Rab = Pab * (545140134*a + 13591409)
    else:
        m = (a + b) // 2
        Pam, Qam, Ram = binary_split(a, m)
        Pmb, Qmb, Rmb = binary_split(m, b)
        
        Pab = Pam * Pmb
        Qab = Qam * Qmb
        Rab = Qmb * Ram + Pam * Rmb
    return Pab, Qab, Rab


def chudnovsky(n):
    """Chudnovsky algorithm."""
    P1n, Q1n, R1n = binary_split(1, n)
    
    print(f"n = {(426880 * decimal.Decimal(10005).sqrt() * Q1n)}")
    print(f"d = {(13591409*Q1n + R1n)}")
    
    return (426880 * decimal.Decimal(10005).sqrt() * Q1n) / (13591409*Q1n + R1n)

decimal.getcontext().prec = 105 # number of digits of decimal precision
print(f"1 = {chudnovsky(105)}")  # 3.141592653589793238462643384