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What is the difference between NaN and None?
...n reason to use NaN (over None) is that it can be stored with numpy's float64 dtype, rather than the less efficient object dtype, see NA type promotions.
# without forcing dtype it changes None to NaN!
s_bad = pd.Series([1, None], dtype=object)
s_good = pd.Series([1, np.nan])
In [13]: s_bad.dtype...
Comparing object properties in c# [closed]
...oblems with overriding .Equals() because i'm trying to implement this on a base class that gets inherited... because I don't know the keys for the class this'll be run against, i can't implement a decent override for GetHasCode() (req'd when you override Equals()).
– nailitdown...
How do I choose between Semaphore and SemaphoreSlim?
...
SemaphoreSlim is based on SpinWait and Monitor, so the thread that waits to acquire the lock is burning CPU cycles for some time in hope to acquire the lock prior to yielding to another thread. If that does not happen, then the threads lets t...
How to .gitignore files recursively
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
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(![]+[])[+[]]… Explain why this works
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Do a “git export” (like “svn export”)?
... You're right. I'd forgotten that I was using git config url.<base>.insteadOf to cache the remote repository. I was therefore using a file:// URL in reality. I doubt that git archive could ever work with git:// URLs since it needs to be able to run git-upload-archive at the remote en...
Passing command line arguments in Visual Studio 2010?
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How to start an application without waiting in a batch file?
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Common programming mistakes for Clojure developers to avoid [closed]
...raditional Java hexadecimal values via the 0x prefix. You can also use any base between 2 and 36 by using the "base+r+value" notation, such as 2r101010 or 36r16 which are 42 base ten.
Trying to return literals in an anonymous function literal
This works:
user> (defn foo [key val]
{key va...
Find the Smallest Integer Not in a List
...st in memory. In the form the question was asked, this would require O(N) 64-bit words.)
@Jorn comments that steps 1 through 3 are a variation on counting sort. In a sense he is right, but the differences are significant:
A counting sort requires an array of (at least) Xmax - Xmin counters wh...