예제 #1
0
        static public void Power(BigNumber xx, BigNumber yy, BigNumber rr, int places)
        {
            int       iflag;
            BigNumber tmp8        = new BigNumber();
            BigNumber tmp9        = new BigNumber();
            int       M_size_flag = BigNumber.GetSizeofInt();

            if (yy.signum == 0)
            {
                BigNumber.Copy(BigNumber.One, rr);
                return;
            }

            if (xx.signum == 0)
            {
                BigNumber.SetZero(rr);
                return;
            }

            if (BigNumber.IsInteger(yy) > 0)
            {
                iflag = 0;

                if (M_size_flag == 2)            /* 16 bit compilers */
                {
                    if (yy.exponent <= 4)
                    {
                        iflag = 1;
                    }
                }
                else                             /* >= 32 bit compilers */
                {
                    if (yy.exponent <= 7)
                    {
                        iflag = 1;
                    }
                }

                if (iflag > 0)
                {
                    String sbuf = BigNumber.ToIntString(yy);
                    int    Exp  = Convert.ToInt32(sbuf);
                    BigNumber.IntPow(places, xx, Exp, rr);
                    return;
                }
            }

            tmp8 = new BigNumber();
            tmp9 = new BigNumber();

            BigNumber.Log(xx, tmp9, (places + 8));
            BigNumber.Mul(tmp9, yy, tmp8);
            BigNumber.Exp(tmp8, rr, places);
        }