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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
When using summarise with plyr 's ddply 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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Define preprocessor macro through CMake?
How do I define a preprocessor variable through CMake?
3 Answers
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How to test if one java class extends another at runtime?
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Are you looking for:
Super.class.isAssignableFrom(Sub.class)
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Install parent POM without building Child modules
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The '-N' or '--non-recursive' option means do not recurse into sub-projects.
– STB Land
Jun 10 '12 at 12:51
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S3 Error: The difference between the request time and the current time is too large
I have error The difference between the request time and the current time is too large when call method amazons3.ListObjects
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How can I make git show a list of the files that are being tracked?
...n I make git show a list of the files that are being tracked in the repository?
4 Answers
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Why doesn't println! work in Rust unit tests?
... happens because Rust test programs hide the stdout of successful tests in order for the test output to be tidy. You can disable this behavior by passing the --nocapture option to the test binary or to cargo test:
#[test]
fn test() {
println!("Hidden output")
}
Invoking tests:
% rustc --test ma...
Difference between Pragma and Cache-Control headers?
...to prevent the client from caching the response. Older clients may not support HTTP/1.1 which is why that header is still in use.
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How do I print the type or class of a variable in Swift?
Is there a way to print the runtime type of a variable in swift? For example:
34 Answers
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What is the difference between ndarray and array in numpy?
...ng of numpy.ndarray:
Arrays should be constructed using array, zeros or empty ... The parameters given here refer to a
low-level method (ndarray(...)) for instantiating an array.
Most of the meat of the implementation is in C code, here in multiarray, but you can start looking at the ndar...