Calculate Pi digits up to 10^9.
This Python program use Decimal module to calculate Pi with desired precision. On my 2018 MacBook Pro, it can calculate Pi to 10^9 digits in a week. More digits were not been tested.
This program only use single thread so it can only test single core performance.
There are 3 different algorithms to cross check the result.
All results will be stored into different .txt files for further use.