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Group by multiple columns in dplyr, using string vector input

... Does the call to one_of() do anything here? I think it is redundant in this context, as the expression is wrapped in a call to vars(). – knowah Aug 15 '19 at 14:13 ...
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How to fix “Attempted relative import in non-package” even with __init__.py

...ry to execute the above shell command, the fact that you need __init__.pys all the way down, and the __package__-modifying trickery (described below by BrenBarn) needed to allow these imports for executable scripts (e.g. when using a shebang and doing ./my_script.py at the Unix shell) would all be u...
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What exactly are iterator, iterable, and iteration?

...loop, or map, or a list comprehension, etc. in Python, the next method is called automatically to get each item from the iterator, thus going through the process of iteration. A good place to start learning would be the iterators section of the tutorial and the iterator types section of the standar...
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What does if __name__ == “__main__”: do?

...ngs: it sets a few special variables like __name__, and then it executes all of the code found in the file. Let's see how this works and how it relates to your question about the __name__ checks we always see in Python scripts. Code Sample Let's use a slightly different code sample to explore ho...
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What is a None value?

...n't write the sticker "F", there was already an F sticker on the None, and all you did was move it, from None to "fork". So when you type F = None, you're "reset[ting] it to its original, empty state", if we decided to treat None as meaning empty state. I can see what he's getting at, but that's a...
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How is pattern matching in Scala implemented at the bytecode level?

...atterns like or patterns and combinations like "case Foo(45, x)", but generally those are just logical extensions of what I just described. Patterns can also have guards, which are additional constraints on the predicates. There are also cases where the compiler can optimize pattern matching, e.g...
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Find all packages installed with easy_install/pip?

Is there a way to find all Python PyPI packages that were installed with easy_install or pip? I mean, excluding everything that was/is installed with the distributions tools (in this case apt-get on Debian). ...
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How to get a function name as a string?

In Python, how do I get a function name as a string, without calling the function? 12 Answers ...
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Arduino Sketch upload issue - avrdude: stk500_recv(): programmer is not responding

...it works. I figured the packets were some attempt at a hand-shake. So basically, I solved it using Google, patience and futzing around with the board! – hoipolloi Jan 12 '14 at 18:16 ...
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Setting custom UITableViewCells height

...ulate the cell height needed and return that calculated value here to make all cells visible – Vinayak GH Jan 11 '16 at 7:39 add a comment  |  ...