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Transpose/Unzip Function (inverse of zip)?

...'d', 4)]) [('a', 'b', 'c', 'd'), (1, 2, 3, 4)] The way this works is by calling zip with the arguments: zip(('a', 1), ('b', 2), ('c', 3), ('d', 4)) … except the arguments are passed to zip directly (after being converted to a tuple), so there's no need to worry about the number of arguments g...
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How do I replace NA values with zeros in an R dataframe?

...then assign it to the location/name on the left. In this case, we aren't really "doing" anything - just making zeroes. The left side is saying: look at the d object, inside the d object (the square brackets), find all the elements that return TRUE (is.na(d) returns a logical for each element). Once...
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Python integer incrementing with ++ [duplicate]

...I've looked back at my VB6 days and thought, "What modern language doesn't allow incrementing with double plus signs?": 7 A...
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Location of my.cnf file on macOS

... This thread on the MySQL forum says: By default, the OS X installation does not use a my.cnf, and MySQL just uses the default values. To set up your own my.cnf, you could just create a file straight in /etc. OS X provides example configuration files at /usr/local/mysql/support-files/...
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Match multiple cases classes in scala

... matcher(l: Foo): String = { l match { case A() => "A" case B(_) | C(_) => "B" case _ => "default" } } If you must, must, must extract the parameter and treat them in the same code block, you could: def matcher(l: Foo): String = { l match { case A() => "A" ca...
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How should I validate an e-mail address?

...ache.commons.validator.routines.EmailValidator) (?:[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*|"(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21\x23-\x5b\x5d-\x7f]|\\[\x01-\x09\x0b\x0c\x0e-\x7f])*")@(?:(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?|\[(?:(?:25[0-...
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Check if a variable is a string in JavaScript

...ing both typeof and instanceof feels like good advice if your code may be called by others'. @MarkAmery's postmessage edge case matters if you're asking "what was I just postmessaged?" - but you'd expect that to be handled at the interface and not allowed to propagate. Elsewhere, it seems correct t...
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What do ellipsis […] mean in a list?

... an infinite loop of references, so it decided to cut it short, it's not really infinite. And no, it's not really useful besides a thought experiment :) – Óscar López Jun 18 '13 at 3:44 ...
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Priority queue in .Net [closed]

...st int GrowFactor = 2; private const int MinGrow = 1; private int _capacity = InitialCapacity; private T[] _heap = new T[InitialCapacity]; private int _tail = 0; public int Count { get { return _tail; } } public int Capacity { get { return _capacity; } } protected Comp...
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Using curl to upload POST data with files

... I think its really useful. public function postFile() { $file_url = "test.txt"; //here is the file route, in this case is on same directory but you can set URL too like "http://examplewebsite.com/test.txt" $eol = "\r\n"; //default line-break for mime type $BOUNDARY = m...