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filter for complete cases in data.frame using dplyr (case-wise deletion)

... are a lot of variables and b) impossible when the variable names are not known (e.g. in a function that processes any data.frame). ...
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Understanding the Event Loop

...ing handled like they would in a thread-per-connection concurrency model. Now about "executing setTimeouts", when you invoke setTimeout, all node does is basically update a data structure of functions to be executed at a time in the future. It basically has a bunch of queues of stuff that needs doi...
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How to stage only part of a new file with git?

I love git add --interactive . It is now part of my daily workflow. 5 Answers 5 ...
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configure: error: C compiler cannot create executables

... Command line Tools packages ars now available at: developer.apple.com/downloads – Danny D'Amours Sep 11 '14 at 23:56 3 ...
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Using jQuery to test if an input has focus

... CSS :hover using the $(#element).hover() method. The only problem is, now that jQuery handles both the form focus() and hover() , when an input has focus then the user moves the mouse in and out, the border goes away. ...
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How to set initial value and auto increment in MySQL?

...ples that used these statements in a similar way, and they make more sense now. Thank you. – Michael Hoffmann Oct 21 '16 at 0:50 1 ...
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Interfaces — What's the point?

...e is an IPizza you can use IPizza wherever you handle an instance of an unknown pizza type. Any instance whose type inherits from IPizza is guaranteed to be orderable, as it has an Order() method. Python is not statically-typed, therefore types are kept and looked up at runtime. So you can try call...
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Optional query string parameters in ASP.NET Web API

... This issue has been fixed in the regular release of MVC4. Now you can do: public string GetFindBooks(string author="", string title="", string isbn="", string somethingelse="", DateTime? date= null) { // ... } and everything will work out of the box. ...
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how to solve “ruby installation is missing psych” error?

...ven though it was successfully installed, it complained about libyaml. and now every time i wanna install a gem (say rails) this warning shows up: ...
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Docker build “Could not resolve 'archive.ubuntu.com'” apt-get fails to install anything

...un Docker build on various files which previously worked before, which are now no longer working. 14 Answers ...