/*  sxcbmpi.cpp  by K.Tsuru  */
// function ID 5104     BRADIX
/*********************
SDecimal class
pi by Machin's formula
**********************/
#ifndef SN_H
#include "sn.h"
#endif

SDecimal BMachinPi(){
    SDecimal bpi, bpi2;

    bpi = Batan2(1, 5);     // bpi = atan(1/5);
    XsMult(bpi, 16, bpi);   // bpi *= 16;
    bpi2 = Batan2(1, 239);  // bpi2 = atan(1/239);
    XsMult(bpi2, 4, bpi2);  // bpi2 *= 4;
    XXSub(bpi, bpi2, bpi);  // bpi -= bpi2;
    return bpi;
}