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Group by multiple columns in dplyr, using string vector input
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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...
What does the 'b' character do in front of a string literal?
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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
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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...
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.
– ...
set date in input type date
...swered Nov 10 '12 at 14:30
int32_tint32_t
4,51511 gold badge1919 silver badges1616 bronze badges
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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 do I export UIImage array as a movie?
...catorDefault, frameSize.width,
frameSize.height, kCVPixelFormatType_32ARGB, (CFDictionaryRef) options,
&pxbuffer);
NSParameterAssert(status == kCVReturnSuccess && pxbuffer != NULL);
CVPixelBufferLockBaseAddress(pxbuffer, 0);
void *pxdata = CVPixelBufferGetBa...
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="...
Case insensitive string compare in LINQ-to-SQL
... server data type by using one of the following;
varchar(4000) COLLATE SQL_Latin1_General_CP1_CS_AS
or
nvarchar(Max) COLLATE SQL_Latin1_General_CP1_CS_AS
Note: The ‘CS’ in the above collation types means ‘Case Sensitive’.
This can be entered in the “Server Data Type” field when ...
addEventListener vs onclick
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@Gaurav_soni No. The name of the function and all the code it contains are already exposed in the javascript file, which is in plaintext. Anyone can open a web console and execute or manipulate any javascript. If your javascript con...