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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
...function, empty categories are dropped by default. You can change this behavior by adding .drop = FALSE . However, this doesn't work when using summarise with dplyr . Is there another way to keep empty categories in the result?
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Get size of an Iterable in Java
I need to figure out the number of elements in an Iterable in Java.
I know I can do this:
10 Answers
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How to split strings across multiple lines in CMake?
I usually have a policy in my project, to never create lines in text files that exceed a line length of 80, so they are easily editable in all kinds of editors (you know the deal). But with CMake I get the problem that I do not know how to split a simple string into multiple lines to avoid one huge ...
Checking if all elements in a list are unique
What is the best way (best as in the conventional way) of checking whether all elements in a list are unique?
14 Answers
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Why XML-Serializable class need a parameterless constructor
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How do I quickly rename a MySQL database (change schema name)?
The MySQL manual at MySQL covers this.
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How exactly does __attribute__((constructor)) work?
It seems pretty clear that it is supposed to set things up.
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How to install Java SDK on CentOS?
I have CentOS 5, but I don't know the steps to install Java SDK on Linux.
12 Answers
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Undocumented NSURLErrorDomain error codes (-1001, -1003 and -1004) using StoreKit
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How to only get file name with Linux 'find'?
I'm using find to all files in directory, so I get a list of paths. However, I need only file names. i.e. I get ./dir1/dir2/file.txt and I want to get file.txt
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