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Sample random rows in dataframe
...3677
5 0.4180331 -1.2592415
6 0.7572246 -0.5463655
7 -0.8996483 0.4231117
8 -1.0356774 -0.1640883
9 -0.3983045 0.7157506
10 -0.9060305 2.3234110
Then select some rows at random:
> df[sample(nrow(df), 3), ]
X1 X2
9 -0.3983045 0.7157506
2 -1.1334614 -0.1973846
10 ...
Tick symbol in HTML/XHTML
...pt X (poorly supported as of 2017)
⮽ (⚠ hex: ⮽ / dec: ⮽): ballot box with light X (poorly supported as of 2017)
???? (⚠ hex: 🗵 / dec: 🗵): ballot box with script X (poorly supported as of 2017)
???? (⚠ hex: 🗹 / dec: 🗹): bal...
“X does not name a type” error in C++
... // now that foo is defined, we can read that reference:
fr.fooInt = 111605;
fr.foDouble = 123.456;
}
By forward declaring User, MyMessageBox can still form a pointer or reference to it:
class User; // let the compiler know such a class will be defined
class MyMessageBox
{
public:
...
How can I replace text with CSS?
...
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111 silver badge
answered Jun 18 '13 at 3:51
Steven PennySteven Penny
76.1k454...
How to remove last n characters from every element in the R vector
...ter notation.
See here for more information on regex quantifiers:
https://www.regular-expressions.info/refrepeat.html
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Why is Scala's immutable Set not covariant in its type?
...
at http://www.scala-lang.org/node/9764 Martin Odersky writes:
"On the issue of sets, I believe the non-variance stems also from the implementations. Common sets are implemented as hashtables, which are non-variant arrays of the key...
How can I link to a specific glibc version?
...sing a glibc-new => glibc-old cross-compiler.
According to the http://www.trevorpounds.com blog post Linking to Older Versioned Symbols (glibc), it is possible to to force any symbol to be linked against an older one so long as it is valid by using the the same .symver pseudo-op that is used fo...
Generating an Excel file in ASP.NET [closed]
...="urn:schemas-microsoft-com:office:spreadsheet"
xmlns:html="http://www.w3.org/TR/REC-html40">
<DocumentProperties xmlns="urn:schemas-microsoft-com:office:office">
<Author>Your_name_here</Author>
<LastAuthor>Your_name_here</LastAuthor>
<Cr...
How to remove a single, specific object from a ConcurrentBag?
...
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111 silver badge
answered Mar 17 '16 at 14:21
LarryLarry
16.2k88 gold badges68...
How do I get the AM/PM value from a DateTime?
...
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answered Oct 24 '11 at 12:05
XikiryoXXikiryoX
1,59811 gold ba...