
NaN是什么 NaN == NaN 的结果是什么?为什么? - 知乎
NaN与任何其他值(包括NaN本身)进行比较的结果都是false,包括NaN == NaN。 这是因为NaN被定义为不等于任何其他值,甚至不等于它自己。 这是由于NaN的特殊性质导致的。 NaN的比较结果 …
floating point - Why is NaN not equal to NaN? - Stack Overflow
NaN is designed to propagate through all calculations, infecting them like a virus, so if somewhere in your deep, complex calculations you hit upon a NaN, you don't bubble out a seemingly sensible …
What is NaN (Not a Number) in the words of a beginner?
Dec 14, 2019 · What is a NaN value or NaN exactly (in the words of a non-math professor)? Let's suppose you're working with real numbers - numbers like 1, π, e, -137, 6.626, etc. In the land of real …
How do you check that a number is NaN in JavaScript?
Apr 16, 2010 · 182 I just came across this technique in the book Effective JavaScript that is pretty simple: Since NaN is the only JavaScript value that is treated as unequal to itself, you can always …
javascript - Why is NaN === NaN false? - Stack Overflow
JavaScript automatic type conversion convert NaN into number, so checking if a number is not a number will always b false. and NaN !== NaN will be true.
javascript - Is NaN equal to NaN? - Stack Overflow
Aug 8, 2011 · 37 It's a special case, NaN is the only thing in Javascript not equal to itself. Although the other answers about strings vs the NaN object are right too.
python - How to check for NaN values - Stack Overflow
float('nan') represents NaN (not a number). But how do I check for it?
python - What is inf and nan? - Stack Overflow
Jul 13, 2013 · nan stands for Not A Number, and this is not equal to 0. Although positive and negative infinity can be said to be symmetric about 0, the same can be said for any value n, meaning that the …
What is the difference between NaN and NA? - Cross Validated
I would like to know why some languages like R has both NA and NaN. What are the differences or are they equally the same? Is it really needed to have NA?
What's the difference between nan, NaN and NAN - Stack Overflow
Jul 24, 2013 · In numpy there are nan, NaN and NAN. What's the sense of having all three, do they differ or any of these can be used interchangeably?