/*  sxcspi.cpp  by K.Tsuru  */
// function ID 5106   BRADIX
/****************************************************
SDecimal and SDouble class
pi by Stormer's formura
pi/4 = 6*arctan(1/8) + 2*arctan(1/57) + arctan(1/239)
*****************************************************/
#ifndef SN_H
#include "sn.h"
#endif
SDecimal BStomerPi(){
    SDecimal  pi, y;

    XsMult(Batan2(1, 8), 6, pi);        // 6*atan(1/8)
    XsMult(Batan2(1, 57), 2, y);        // y = 2*atan(1/57)
    XXAdd(pi, y, pi);
    y = Batan2(1, 239);
    XXAdd(pi, y, pi);
    XsMult(pi, 4, pi);

    return pi;
}
// function ID 3509   DRADIX
SDouble StomerPi(){
    return BStomerPi().ConvToDec();
}