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Drop all duplicate rows across multiple columns in Python Pandas
The pandas drop_duplicates function is great for "uniquifying" a dataframe. However, one of the keyword arguments to pass is take_last=True or take_last=False , while I would like to drop all rows which are duplicates across a subset of columns. Is this possible?
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Difference between binary tree and binary search tree
Can anyone please explain the difference between binary tree and binary search tree with an example ?
12 Answers
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Why do function pointer definitions work with any number of ampersands '&' or asterisks '*'?
...foo)() = foo; works: foo is implicitly converted into a pointer to itself and that pointer is assigned to p1_foo.
The unary &, when applied to a function, yields a pointer to the function, just like it yields the address of an object when it is applied to an object. For pointers to ordinary f...
What is the purpose of the single underscore “_” variable in Python?
...nt) in an interactive
interpreter session. This precedent was set by the standard CPython
interpreter, and other interpreters have followed suit
As a general purpose "throwaway" variable name to indicate that part
of a function result is being deliberately ignored (Conceptually, it is being discarde...
Prevent direct access to a php include file
...or may not fully control" situation is to put your includes in a directory and deny access to that directory in your .htaccess file. To save people the trouble of Googling, if you're using Apache, put this in a file called ".htaccess" in the directory you don't want to be accessible:
Deny from all
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How to validate phone numbers using regex
...ogether a comprehensive regex to validate phone numbers. Ideally it would handle international formats, but it must handle US formats, including the following:
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Data Modeling with Kafka? Topics and Partitions
...type of consumer so in the example above, I would just have a single topic and if you´ll decide to push some other kind of data through Kafka, you can add a new topic for that later.
Topics are registered in ZooKeeper which means that you might run into issues if trying to add too many of them, e....
What is the difference between a dialog being dismissed or canceled in Android?
...ys, what is the difference between a dialog being dismissed or canceled in Android?
4 Answers
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Always pass weak reference of self into block in ARC?
...am a little confused about block usage in Objective-C. I currently use ARC and I have quite a lot of blocks in my app, currently always referring to self instead of its weak reference. May that be the cause of these blocks retaining self and keeping it from being dealloced ? The question is, sho...
Which are more performant, CTE or temporary tables?
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I'd say they are different concepts but not too different to say "chalk and cheese".
A temp table is good for re-use or to perform multiple processing passes on a set of data.
A CTE can be used either to recurse or to simply improved readability.
And, like a view or inline table valued functio...