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Select multiple columns in data.table by their numeric indices
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No problem. Compare also dt[,"a"] and dt[,"a", with=FALSE] to see what a helpful option it really is.
– Josh O'Brien
Nov 14 '12 at 17:41
3
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How do I resize an image using PIL and maintain its aspect ratio?
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Like it says, the example was from the pil documentation, and that example (still) doesn't use the antialias flag. Since it's probably what most people would want, though, I added it.
– gnud
Dec 8 '11 at 8:29
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What's the maximum value for an int in PHP?
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integers. Integer size can be
determined using the constant
PHP_INT_SIZE, and maximum value using
the constant PHP_INT_MAX since PHP
4.4.0 and PHP 5.0.5.
64-bit platforms usually have a maximum value of about 9E18, except on Windows prior to PHP 7, where it was always 32 bit.
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When should TaskCompletionSource be used?
...n NuGet which allows the async/await keywords in .NET 4.0 projects (VS2012 and higher is recommended).
– Erik
Feb 1 '14 at 18:41
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Array versus linked-list
...er of changing what points to what. Shuffling an array is more complicated and/or takes more memory.
As long as your iterations all happen in a "foreach" context, you don't lose any performance in iteration.
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JFrame in full screen Java
I will be doing a project soon and I will have to use full screen mode in it.
13 Answers
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How do I sort an observable collection?
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Sorting an observable and returning the same object sorted can be done using an extension method. For larger collections watch out for the number of collection changed notifications.
I have updated my code to improve performance (thanks to nawfal)...
How to use the same C++ code for Android and iOS?
Android with NDK has support to C/C++ code and iOS with Objective-C++ has support too, so how can I write applications with native C/C++ code shared between Android and iOS?
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In which scenario do I use a particular STL container?
...p on STL containers in my book on C++, specifically the section on the STL and its containers. Now I do understand each and every one of them have their own specific properties, and I'm close to memorizing all of them... But what I do not yet grasp is in which scenario each of them is used.
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How to add leading zeros for for-loop in shell? [duplicate]
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Best answer, and it avoids using clumsy external commands (like 'seq', not necessary in proper Bash). Helped me.
– Scott Prive
Jan 28 '15 at 20:31
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