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How can I obtain the element-wise logical NOT of a pandas Series?
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Wierd, I actually tested the tilde as it was mentioned in the documentation, but it didn't perform the same as np.invert :S
– root
Apr 14 '13 at 13:11
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How do I check whether a jQuery element is in the DOM?
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There is a pure-DOM way to do this, which is syntactically more readable, and I imagine very similar in terms of performance: document.contains($foo[0])
– Joel Cross
Dec 1 '15 at 10:16
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If vs. Switch Speed
Switch statements are typically faster than equivalent if-else-if statements (as e.g. descibed in this article ) due to compiler optimizations.
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How to expire session due to inactivity in Django?
...just have to make some urls and views to return relevant data to the ajax calls regarding the session expiry.
when the user opts to "renew" the session, so to speak, all you have to do is set requeset.session['last_activity'] to the current time again
Obviously this code is only a start... but it ...
Using multiple let-as within a if-statement in Swift
...e code inside the if-let block won't be executed.
Note: the clauses don't all have to be 'let' clauses, you can have any series of boolean checks separated by commas.
For example:
if let latitudeDouble = latitude as? Double, importantThing == true {
// latitudeDouble is non-optional in here ...
Sprintf equivalent in Java
...atting with an instance method makes little sense, as it would have to be called like:
String formatted = "%s: %s".format(key, value);
The original Java authors (and .NET authors) decided that a static method made more sense in this situation, as you are not modifying the target, but instead call...
Lost my schema.rb! Can it be regenerated?
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If you run a rake -T it will list all possible rake tasks for your Rails project. One of them is db:schema:dump which will recreate the schema.rb for the Rails app from the database.
bundle exec rake db:schema:dump
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Java abstract interface
...blic void interfacing();
public abstract boolean interfacing(boolean really);
\___.__/
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'----> nor this, are necessary.
}
Interfaces and their methods are implicitly abstract and adding that modifier makes no difference.
Is there other rules tha...
How to return smart pointers (shared_ptr), by reference or by value?
...ilers. I know for a fact that Visual C++ compilers implement RVO even when all optimizations are turned off. And with C++11's move semantics, this concern is even less relevant. (But the only way to be sure is to profile and experiment.)
If you're still not convinced, Dave Abrahams has an article t...
What's the difference between hard and soft floating point numbers?
...t float) in accuracy-critical parts and fast (hard float) in parts where small deviations don't matter.
– PhilLab
May 29 '17 at 12:18
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