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Selecting only numeric columns from a data frame
...ly, even though it's less code
## nums <- sapply(x, is.numeric)
For a more idiomatic modern R I'd now recommend
x[ , purrr::map_lgl(x, is.numeric)]
Less codey, less reflecting R's particular quirks, and more straightforward, and robust to use on database-back-ended tibbles:
dplyr::select_i...
Is there a stopwatch in Java?
...g.time.StopWatch
But it roughly does the same as yours. If you're in for more precision, use
System.nanoTime()
See also this question here:
Time measuring overhead in Java
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How to set a timer in android
... For normal timing operations (ticks, timeouts, etc) it is easier and much more efficient to use Handler."
– Christopher Perry
Nov 5 '11 at 18:42
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How do I put an already-running process under nohup?
... As the question was how to "put it under nohup",disown -h perhaps is the more exact answer: "make disown behave more like nohup (i.e. the jobs will stay in your current shell's process tree until you exit your shell) This allows you to see all the jobs that this shell started." (from [quantprincip...
Why do we need to install gulp globally and locally?
...say that I need to install gulp first globally (with -g flag) and then one more time locally. Why do I need this?
7 Answers...
What is the purpose of the “Prefer 32-bit” setting in Visual Studio and how does it actually work?
... moved. The
default for most .NET projects is again AnyCPU, but there is more than
one meaning to AnyCPU now. There is an additional sub-type of AnyCPU,
“Any CPU 32-bit preferred”, which is the new default (overall, there
are now five options for the /platform C# compiler switch: x86,
...
How to add a new audio (not mixing) into a video using ffmpeg?
...n allows you to manually select streams / tracks. See FFmpeg Wiki: Map for more info.
This example uses -c:v copy to stream copy (mux) the video. No re-encoding of the video occurs. Quality is preserved and the process is fast.
If your input audio format is compatible with the output format then ch...
What does the “yield” keyword do?
...ion arrives here, the generator will be considered empty
# there is no more than two values: the left and the right children
Caller:
# Create an empty list and a list with the current object reference
result, candidates = list(), [self]
# Loop on candidates (they contain only one element at ...
How can I make the tabs work normally on Xcode 4?
...pse). And for me this kind of sucks.
In general, I expect IDE tabs to keep more than 1 file open. So if I click a file in the project tree, I expect that it will switch to the tab I have opened with that file - if I have already opened it. Instead, XCode 4 changes the current tab to the file I click...
Make an Installation program for C# applications and include .NET Framework installer into the setup
... 'Microsoft .NET Framework 4.6.1 (x86 and x64)' to your local machine. For more information, see http://go.microsoft.com/fwlink/?LinkId=616018.
– Chris
Mar 24 '18 at 7:21
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