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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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Is C++ context-free or context-sensitive?
...uring-complete, since it shows a program which is syntactically correct if and only if a given integer is prime.
So I assert that C++ is neither context-free nor context-sensitive.
If you allow arbitrary symbol sequences on both sides of any production, you produce an Type-0 grammar ("unrestricted...
Ruby optional parameters
...his method: e.g. If you're trying to make the default value for scope true and you pass in false, scope ||= true won't work. It evaluates the same as nil and will set it to true
– Joshua Pinter
Nov 10 '11 at 5:32
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How should I escape commas and speech marks in CSV files so they work in Excel?
...en the CSV file in Excel by double clicking it. My data may contain commas and speech marks, so I'm escaping those as follows.
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For-each over an array in JavaScript
...-of loop (ES2015+ only),
Array#forEach (spec | MDN) (or its relatives some and such) (ES5+ only),
a simple old-fashioned for loop,
or for-in with safeguards.
But there's lots more to explore, read on...
JavaScript has powerful semantics for looping through arrays and array-like objects. I've s...
Proper way to rename solution (and directories) in Visual Studio
...1 to be Project2, using a text editor like NotePad.
Restart Visual Studio, and everything will work as before, but with the project in a different directory.
You can also see renaming solution manually or post which describes this manual process.
Advantages
You can make the directory within Win...
Is there a performance difference between i++ and ++i in C++?
We have the question is there a performance difference between i++ and ++i in C?
17 Answers
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Is there a perfect algorithm for chess? [closed]
...s huge. Even a 2 rooks + king has something like 22 possible next moves. And if it takes 6 moves to mate, you're looking at 12,855,002,631,049,216 moves.
Do the math on opening moves. While there's only about 20 opening moves, there are something like 30 or so second moves, so by the third move ...
Set breakpoint in C or C++ code programmatically for gdb on Linux
... I don't know other debuggers, but gdb is pretty flexible about signal handling.
– Cascabel
Dec 1 '10 at 16:25
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How to stop tracking and ignore changes to a file in Git?
...ent git from detecting changes in these files you should also use this command:
git update-index --assume-unchanged [path]
What you probably want to do: (from below @Ryan Taylor answer)
This is to tell git you want your own independent version of the file or folder. For instance, you don't...