public static BigNumber Pow(BigNumber Num1,BigNumber Num2,int precision = 30)
{
//Num1为底，Num2为幂次
//precision默认为保留30位小数
if (Num2 > 0)
{
return Num1.Power(Num2, precision);
}
else if (Num2 <0)
{
Num2 = 0 - Num2;
return 1 / Num1.Power(Num2, precision);
}
else
{
return 1;
}
}
public static string round(string number, int digits, int type)
{
//type为0时四舍五入，1为ground，2为ceiling
int NumOriginLen = number.Length;
char[] digit_dot = { '.' };
string[] NumberBroken;
NumberBroken = number.Split(digit_dot);
if (digits < 0)
{
digits = 0;
}
if (NumberBroken[0].Length == NumOriginLen)
{
if (digits <= 0)
{
return number;
}
else
{
return NumberBroken[0] + ".".PadRight(digits + 1, '0');
}
}
else
{
string decimal_part = " ";
BigNumber zero_point_one = new BigNumber("0.1");
BigNumber one = new BigNumber("1");
if (NumberBroken[1].Length > digits)
{
if (type == 1)
{
decimal_part = NumberBroken[1].Substring(0, digits);
}
else if (type == 2)
{
BigNumber carry = new BigNumber(digits.ToString());
carry = zero_point_one.Power(carry, 200);
BigNumber number_changed = new BigNumber(number);
number_changed = number_changed + carry;
if (digits <= 0)
{
return number_changed.ToString().Substring(0, NumberBroken[0].Length);
}
return number_changed.ToString().Substring(0, NumOriginLen - (NumberBroken[1].Length - digits));
}
else
{
if (Convert.ToInt32(NumberBroken[1].Substring(digits, 1)) > 4)
{
BigNumber carry = new BigNumber(digits.ToString());
carry = zero_point_one.Power(carry, 200);
BigNumber number_changed = new BigNumber(number);
number_changed = number_changed + carry;
return number_changed.ToString().Substring(0, NumOriginLen - (NumberBroken[1].Length - digits));
}
else
{
decimal_part = NumberBroken[1].Substring(0, digits);
}
}
}
else
{
decimal_part = NumberBroken[1].PadRight(digits, '0');
}
if (decimal_part == "")
{
return NumberBroken[0];
}
return NumberBroken[0] + '.' + decimal_part;
}
}