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Select multiple columns in data.table by their numeric indices
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It's a bit verbose, but i've gotten used to using the hidden .SD variable.
b<-data.table(a=1,b=2,c=3,d=4)
b[,.SD,.SDcols=c(1:2)]
It's a bit of a hassle, but you don't lose out on other data.table features (I don't think), so you should still be able to use other important ...
How do I make the return type of a method generic?
...(value, typeof(T));
}
I'm not entirely convinced that all this is a good idea, mind you...
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assign multiple variables to the same value in Javascript
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As @doublejosh said, there are scoping problems you didn't address.
– kstratis
Oct 4 '15 at 7:56
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How to increase font size in a plot in R?
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Did you read help(par) about ps? Does not seem text-related as far as I can tell.
– Dirk Eddelbuettel
Nov 22 '10 at 2:51
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Difference: std::runtime_error vs std::exception()
...proach, offered to you by the authors of the language. As you see, they decided to split all exception types into "runtime errors" and "logic errors" and let you proceed from there with your own exception types. There are, of course, alternative ways to structure that hierarchy, which might be more ...
How to identify platform/compiler from preprocessor macros?
...et for both OS X and iOS. You can #include <TargetConditionals.h> inside #ifdef __APPLE__, which then gives you a TARGET_OS_IPHONE #define.
– Ted Mielczarek
Aug 18 '11 at 11:51
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Any difference between First Class Function and High Order Function
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@Simon I think the key to avoiding confusion is to remember that a language either has first-class functions (you can also talk about "first-class" other things, like first-class classes, etc), or it doesn't. So you never talk about a particular function...
How do I reset the scale/zoom of a web app on an orientation change on the iPhone?
...not setting a maximum-scale in markup.
<meta name="viewport" content="width=device-width, initial-scale=1">
Then disable scalability with javascript on load until gesturestart when you allow scalability again with this script:
if (navigator.userAgent.match(/iPhone/i) || navigator.userAgent...
Can I get chrome-devtools to actually search all JS sources?
...al directory of files which will be available in the Sources file browser sidebar which will also be searchable with the above shortcut.
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Swift - class method which must be overridden by subclass
...ay to make a "pure virtual function" in Swift, ie. one that must be overridden by every subclass, and which, if it is not, causes a compile time error?
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