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Can grep show only words that match search pattern?
... output. This is the default
when there is only one file (or only standard input) to search.
-o, --only-matching
Print only the matched (non-empty) parts of a matching line,
with each such part on a separate output line.
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Enum type constraints in C# [duplicate]
... 's? I'm sure there is a method behind the madness, but I'd like to understand why it's not possible.
6 Answers
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Drop data frame columns by name
...DF) %in% drops)]
Or, alternatively, you can make a list of those to keep and refer to them by name :
keeps <- c("y", "a")
DF[keeps]
EDIT :
For those still not acquainted with the drop argument of the indexing function, if you want to keep one column as a data frame, you do:
keeps <- "y"
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Copy folder recursively, excluding some folders
...ript that will copy the entire contents of a folder including hidden files and folders into another folder, but I want to exclude certain specific folders. How could I achieve this?
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How do I create a basic UIButton programmatically?
...ng the viewDidLoad method, three UIButton s will be created dynamically and its layout or properties are set.
34 Answers...
How to Implement Custom Table View Section Headers and Footers with Storyboard
...g a storyboard we could simply drag a UIView onto the canvas, lay it out and then set it in the tableView:viewForHeaderInSection or tableView:viewForFooterInSection delegate methods.
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How to find out if an item is present in a std::vector?
... @bobobobo: OOP has nothing to do with members vs. non-members. And there is a widespread school of thought that if something does not have to be a member, or when it does not give any advantage when implemented as a member, than it should not be a member; std::vector<>::find() woul...
How can I write output from a unit test?
...e(line) or Console.Write(Line) simply gets skipped over while debugging and the output is never printed. Calls to these functions from within classes I'm using work fine.
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jQuery event to trigger action when a div is made visible
I'm using jQuery in my site and I would like to trigger certain actions when a certain div is made visible.
22 Answers
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How to handle configuration in Go [closed]
I'm new at Go programming, and I'm wondering: what is the preferred way to handle configuration parameters for a Go program (the kind of stuff one might use properties files or ini files for, in other contexts)?
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