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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
...e to go with @Moody_Mudskipper's answer: Using .drop=FALSE can give potentially unexpected results when one or more grouping variables are not coded as factors. See examples below:
library(dplyr)
data(iris)
# Add an additional level to Species
iris$Species = factor(iris$Species, levels=c(levels(ir...
Logging framework incompatibility
I'm building a small Java app and hoping to use logback for logging.
3 Answers
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Boolean operators && and ||
...es the longer form "appropriate for programming control-flow and [is] typically preferred in if clauses."
So you want to use the long forms only when you are certain the vectors are length one.
You should be absolutely certain your vectors are only length 1, such as in cases where they are funct...
Remove duplicate values from JS array [duplicate]
...olution is O(n^2), making it inefficient.
– Casey Kuball
Sep 21 '17 at 16:35
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I really wish in 2...
Git: How to remove file from index without deleting files from any repository
...ware (directly out of a repository).
Keep File as a ‘Default’ and Manually/Automatically Activate It
If it is not completely unacceptable to continue to maintain the configuration file's content in the repository, you might be able to rename the tracked file from (e.g.) foo.conf to foo.conf.de...
How do you set up use HttpOnly cookies in PHP
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With PHP 8's named parameters, we'll finally be able to make the set_cookie call less verbose if we don't need to set the other parameters. For example set_cookie($name, $value, httponly: true).
– Sygmoral
Aug 30 at 15:36
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How to remove the default link color of the html hyperlink 'a' tag?
...erited. This
<a href="http://example.com">link</a> would normally take on the default link or visited color, but has been styled to inherit the color from the paragraph.</p>
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Delete branches in Bitbucket
...icon. Click that, then choose Delete branch. Just be sure you want to drop all the changes there!
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SQL Client for Mac OS X that works with MS SQL Server [closed]
How can I connect to a remote SQL server using Mac OS X? I don't really need a GUI, but it would be nice to have for the color coding and resultset grid. I'd rather not have to use a VM.
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How to generate a random integer number from within a range
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All the answers so far are mathematically wrong. Returning rand() % N does not uniformly give a number in the range [0, N) unless N divides the length of the interval into which rand() returns (i.e. is a power of 2). Furthe...