Question

所以我正在尝试编写一种非常具体的方法来获得定向2D碰撞，这一个双重不断给我一个NaN值。它使用的值都不是NaN，因此它必须是这一行中的值，其中值为

double dX = Math.Sqrt(Math.Pow(collisionCorner.X - playerCorner.X, 2) + 
                      Math.Pow((collisionCorner.X - (2 * playerCorner.Y) + 
                               (thatOnePart * playerCorner.X)) / thatOnePart, 2));

ThatOnePart值对我来说只是一个快捷方式，这是我需要在这里使用很多的东西所以这就是为什么我做了它，如果它很重要我会在这里添加它：

double thatOnePart = ((newPlayerCorner.Y - playerCorner.Y) /
                      (newPlayerCorner.X - playerCorner.X));

更新

我把它全部分解为单独的操作以查看它出错的地方：

double dx1 = collisionCorner.X - playerCorner.X;
        Console.WriteLine("dx1 operation 1: " + dx1);
        dx1 = Math.Pow(dx1, 2);
        Console.WriteLine("dx1 operation 2: " + dx1);

        double dx2 = thatOnePart / playerCorner.X;
        Console.WriteLine("dx2 operation 1: " + dx2);
        dx2 -= playerCorner.Y * 2;
        Console.WriteLine("dx2 operation 2: " + dx2);
        dx2 += collisionCorner.X;
        Console.WriteLine("dx2 operation 3: " + dx2);
        dx2 = dx2 / thatOnePart;
        Console.WriteLine("dx2 operation 4: " + dx2);
        dx2 = Math.Pow(dx2, 2);
        Console.WriteLine("dx2 operation 5: " + dx2);

        double dX = dx1 + dx2;
        Console.WriteLine("dX operation 1: " + dX);
        dX = Math.Sqrt(dX);
        Console.WriteLine("dX operation 2: " + dX);

控制台给了我这个：

dx1操作1：27,1995391845703 dx1操作2：739,814931852976 dx2操作1：8 dx2操作2：8 dx2操作3：8 dx2操作4：NaN dx2操作5：NaN dX操作1：NaN dX操作2：NaN

所以当它被theOnePart划分时会出错，但是在这个例子中thatOnePart的值是8，所以我仍然不知道这里出了什么问题

更新：

所以我在所有这些操作之前为所有使用的值添加了一条写字符，这样你就可以看到它们是什么，代码现在是：

Console.WriteLine("collisionCornerX = " + collisionCorner.X + " thatOnePart = " + thatOnePart + " playerCornerX = " + playerCorner.X + " playerCornerY = " + playerCorner.Y);

        double dx1 = collisionCorner.X - playerCorner.X;
        Console.WriteLine("dx1 operation 1: " + dx1);
        dx1 = Math.Pow(dx1, 2);
        Console.WriteLine("dx1 operation 2: " + dx1);

        double dx2 = thatOnePart / playerCorner.X;
        Console.WriteLine("dx2 operation 1: " + dx2);
        dx2 -= playerCorner.Y * 2;
        Console.WriteLine("dx2 operation 2: " + dx2);
        dx2 += collisionCorner.X;
        Console.WriteLine("dx2 operation 3: " + dx2);
        dx2 = dx2 / thatOnePart;
        Console.WriteLine("dx2 operation 4: " + dx2);
        Console.WriteLine("thatOnePart: " + thatOnePart);
        dx2 = Math.Pow(dx2, 2);
        Console.WriteLine("dx2 operation 5: " + dx2);

        double dX = dx1 + dx2;
        Console.WriteLine("dX operation 1: " + dX);
        dX = Math.Sqrt(dX);
        Console.WriteLine("dX operation 2: " + dX);

并且控制台给了我：

collisionCornerX = 224 
thatOnePart      = 8 
playerCornerX    = 193,6004 
playerCornerY    = 246,0005

dx1 operation 1: 30,3995513916016
dx1 operation 2: 924,132724810625
dx2 operation 1: 8
dx2 operation 2: 8
dx2 operation 3: 8
dx2 operation 4: NaN
    thatOnePart: 8
dx2 operation 5: NaN
 dX operation 1: NaN
 dX operation 2: NaN

更新：

我检查了每个参数的值，这是控制台给我的，它们在整个过程中都保持不变

collisionCornerX = 224 thatOnePart = -8 playerCornerX = 194,4005 
playerCornerY = 227,6004
dx1 operation 1: 29,5995483398438
collisionCornerX = 224 thatOnePart = -8 playerCornerX = 194,4005                     playerCornerY = 227,6004
dx1 operation 2: 876,133261922747
collisionCornerX = 224 thatOnePart = -8 playerCornerX = 194,4005 playerCornerY = 227,6004
dx2 operation 1: -8
collisionCornerX = 224 thatOnePart = -8 playerCornerX = 194,4005 playerCornerY = 227,6004
dx2 operation 2: -8
collisionCornerX = 224 thatOnePart = -8 playerCornerX = 194,4005 playerCornerY = 227,6004
dx2 operation 3: -8
collisionCornerX = 224 thatOnePart = -8 playerCornerX = 194,4005 playerCornerY = 227,6004
dx2 operation 4: NaN
collisionCornerX = 224 thatOnePart = -8 playerCornerX = 194,4005 playerCornerY = 227,6004
thatOnePart: -8
dx2 operation 5: NaN
collisionCornerX = 224 thatOnePart = -8 playerCornerX = 194,4005 playerCornerY = 227,6004
dX operation 1: NaN
collisionCornerX = 224 thatOnePart = -8 playerCornerX = 194,4005 playerCornerY = 227,6004
dX operation 2: NaN
collisionCornerX = 224 thatOnePart = -8 playerCornerX = 194,4005 playerCornerY = 227,6004

Answer 1

如果您咨询documentation of the Sqrt method，可以找到：

您可以在方法中输入负输入或NaN输入作为参数 Devision by 0将导致正无穷大：

NAN

查看documentation of the Pow method如果输入(x,y)为{{1}}，它将返回{{1}}：

x＆lt; 0但不是NegativeInfinity; y不是整数，NegativeInfinity或PositiveInfinity。

或

x = -1; y = NegativeInfinity或PositiveInfinity。

或

x或y = NaN。

所以其中一个案例就是它。

为什么这是双NaN（C＃）

1 个答案: