奇怪的1。在VB.NET#印第安纳错误-Strange-1.#INDerrorinVB.NET

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You can figure out what's going on by trying following:

你可以通过以下步骤来弄清楚发生了什么:

Console.WriteLine(-1 ^ 0.5)

It prints -1, but in fact it is the same as sqrt(-1) which does not have a result in Real numbers. That's weird, isn't it? So what's going on here?

它输出-1，但实际上它和sqrt(-1)是一样的，它不会产生实数。这是奇怪的,不是吗?这是怎么回事?

^ has higher precedence than -, so -1 ^ 0.5 is actually -(1 ^ 0.5). That's why it prints -1.

比- - - - - - ^具有更高的优先级,所以1 ^ 0.5实际上是-(1 ^ 0.5)。这就是它打印-1的原因。

You can check the precedence list here: Operator Precedence in Visual Basic

您可以在这里检查优先列表:Visual Basic中的操作符优先级

The same happens with your code. -0.78125 ^ 2.5 is actually interpreted as -(0.78125 ^ 2.5) which is valid, but if you do (-0.78125 + 0) ^ 2.5 (or even (-0.78125) ^ 2.5) it's not valid anymore, because it would require calculating square root from negative value. That's why you're getting NaN (or -1#IND).

代码也是如此。-0.78125 ^ 2.5实际上是解释为——(0.78125 ^ 2.5)是有效的,但是如果你2.5(-0.78125 + 0)^(甚至(-0.78125)^ 2.5)不再有效,因为这需要计算平方根的负面价值。这就是为什么你会得到NaN(或-1#IND)。