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Group by multiple columns in dplyr, using string vector input
...
Since this question was posted, dplyr added scoped versions of group_by (documentation here). This lets you use the same functions you would use with select, like so:
data = data.frame(
asihckhdoydkhxiydfgfTgdsx = sample(LETTERS[1:3], 100, replace=TRUE),
a30mvxigxkghc5cdsvxvyv0ja = s...
How to attribute a single commit to multiple developers?
...d by GitHub.
– llrs
Jan 31 '18 at 8:06
I wrote a simple git plugin to make it easier to manage these Co-authored-by tr...
Convert.ChangeType() fails on Nullable Types
...a series of blog posts including this at http://www.endswithsaurus.com/2010_07_01_archive.html (Scroll down to the Addendum, @JohnMacintyre actually spotted the bug in my original code which led me down the same path you're on now). I have a couple of small modifications since that post that includ...
What does the 'b' character do in front of a string literal?
...
Actually, if you've imported unicode_literals from __future__, this will "reverse" the behavior for this particular string (in Python 2.x)
– Romuald Brunet
Mar 14 '13 at 16:27
...
nonlocal keyword in Python 2.x
... @BobStein Sorry, I don't really understand what you mean. But by adding __slots__ = () and creating an object instead of using the class, e.g. context.z = 3 would raise an AttributeError. It is possible for all classes, unless they inherit from a class not defining slots.
– ...
Change project name on Android Studio
...can!
– Ilya Gazman
Sep 18 '15 at 11:06
6
Still works (Android Studio 2.3). Had to do "Clean Proje...
Is it pythonic to import inside functions?
...te the circular dependency)
Inserting a pdb breakpoint: import pdb; pdb.set_trace() This is handy b/c I don't want to put import pdb at the top of every module I might want to debug, and it easy to remember to remove the import when I remove the breakpoint.
Outside of these two cases, it's a good ...
How does std::move() transfer values into RValues?
...ch I cleaned up a little bit):
template <typename T>
typename remove_reference<T>::type&& move(T&& arg)
{
return static_cast<typename remove_reference<T>::type&&>(arg);
}
Let's start with the easier part - that is, when the function is called wi...
Why split the tag when writing it with document.write()?
...ecx.images-amazon.com/images/G/01/javascripts/lib/jquery/jquery-1.2.6.pack._V265113567_.js"></script>');
}
// -->
</script>
...but to be honest, using document.write is not something I would consider best practice. Why not manipulating the DOM directly?
<script type="...
Why does JavaScript only work after opening developer tools in IE once?
...lly: stackoverflow.com/questions/13391563/…
– user1062589
Nov 16 '16 at 22:51
2
this should be ...