Question

这里的代码是:

    static void Main(string[] args)
    { 
        int xd2 = 5;

        for (double xd = (double)xd2; xd <= 6; xd += 0.01)
        {
            Console.WriteLine(xd);
        }

    }

and here s the output: enter image description here

I want to keep on adding 0.01 (as You can see on the screen, sometimes it happens to add 0.99999) Thanks

Answer 1

使用"http://msdn.microsoft.com/ en- us/library/ system. decital.aspx"\\ code> decitimal,如果你想保持这种准确性的话。

浮点类型不能准确地代表某些数值。我建议阅读 < a href="http://docs.oracle.com/cd/E19957-01/806-3568/ncg_goldberg.html> 每个计算机科学家应该知道什么关于浮点亚学的全面解释。

decimal xd2 = 5m;

for (decimal xd = xd2; xd <= 6m; xd += 0.01m)
{
    Console.WriteLine(xd);
}

Answer 2

不,这是双倍工作的方法... 尝试用小数数代替小数

 int xd2 = 5;

 for (decimal xd = (decimal)xd2; xd <= 6; xd += 0.01M)
 {
     Console.WriteLine(xd);
 }

如果您想要继续使用双倍, 但只注意小数点后两个位数使用...

int xd2 = 5;

for (double xd = (double)xd2; xd <= 6; xd += 0.01)
{
   Console.WriteLine(Math.Round(xd,2));
}

Answer 3

This is because double is float pointing and this arithmetic is not precise. You can use decimal instead, like this:

 static void Main(string[] args)
    {
        int xd2 = 5;

        for (decimal xd = (decimal)xd2; xd <= 6; xd += 0.01M)
        {
            Console.WriteLine(xd);
        }
        Console.ReadLine();
    }

也见此条:关于.NET 的多精度问题。

Answer 4

如果可能的话,你应该总是使用绝对的而不是迭代计算来消除这些四舍五入的错误:

public static void Main(string[] args)
{
    int xd2 = 5;

    for (int i = 0; i < 100; ++i) {
        Console.WriteLine(xd2 + i * 0.01);
    }
}

友情链接