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- 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 answer Otherwise by identity NaN NaN should equal 1, along with all the other consequences like (NaN NaN)==1, (NaN*1)==NaN, etc
- python - How to check for NaN values - Stack Overflow
float('nan') represents NaN (not a number) But how do I check for it?
- How do you check that a number is NaN in JavaScript?
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 test if a value is NaN by checking it for equality to itself:
- 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
- python - How to check if particular value (in cell) is NaN in pandas . . .
>>> df iloc[1,0] nan So, why is the second option not working? Is it possible to check for NaN values using iloc? Editor's note: This question previously used pd np instead of np and ix in addition to iloc, but since these no longer exist, they have been edited out to keep it short and clear
- javascript - Is NaN equal to NaN? - Stack Overflow
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
- 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?
- python - What is inf and nan? - Stack Overflow
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 result of adding the two yields nan This idea is discussed in this math se question
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