/*  sxckspi.cpp  by K.Tsuru  */
// function ID 5107   BRADIX
/********************************************************
pi by Klingenstierna's formura
pi/4 = 8*arctan(1/10) - arctan(1/239) -4*arctan(1/515)
*********************************************************/
#ifndef SN_H
#include "sn.h"
#endif
SDecimal BKlingenstiernaPi(){
    SDecimal bpi, u;

    bpi = Batan2(1, 10);
    XsMult(bpi, 8, bpi);
    u = Batan2(1, 239);
    XXSub(bpi, u, bpi);
    u = Batan2(1, 515);
    XsMult(u, 4, u);
    XXSub(bpi, u, bpi);
    XsMult(bpi, 4, bpi);
    return bpi;
}
// function ID 3510   DRADIX
SDouble KlingenstiernaPi(){
    return BKlingenstiernaPi().ConvToDec();
}