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Pandas: create two new columns in a dataframe with values calculated from a pre-existing column
...he top answer is flawed in my opinion. Hopefully, no one is mass importing all of pandas into their namespace with from pandas import *. Also, the map method should be reserved for those times when passing it a dictionary or Series. It can take a function but this is what apply is used for.
So, if ...
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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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...
How can I decompress a gzip stream with zlib?
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To decompress a gzip format file with zlib, call inflateInit2 with the windowBits parameter as 16+MAX_WBITS, like this:
inflateInit2(&stream, 16+MAX_WBITS);
If you don't do this, zlib will complain about a bad stream format. By default, zlib creates streams with ...
What is the list of supported languages/locales on Android?
...n_LS [English (Lesotho)]
en_MG [English (Madagascar)]
en_MH [English (Marshall Islands)]
en_MO [English (Macau)]
en_MP [English (Northern Mariana Islands)]
en_MS [English (Montserrat)]
en_MT [English (Malta)]
en_MU [English (Mauritius)]
en_MW [English (Malawi)]
en_NA [English (Namibia)]
en_NF [Engli...
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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