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For each row in an R dataframe
I have a dataframe, and for each row in that dataframe I have to do some complicated lookups and append some data to a file.
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UIView's frame, bounds, center, origin, when to use what?
UIView has the properties frame , bounds , center , and origin , and they all seem to be interrelated. Most of the time, I deal with frame when setting the position and size of a UIView . I understand that frame is using global coordinate system and bounds is using coordinate of the lo...
Why is String.chars() a stream of ints in Java 8?
...d, the design decision behind this was to prevent the explosion of methods and classes.
Still, personally I think this was a very bad decision, and there should, given they do not want to make CharStream, which is reasonable, different methods instead of chars(), I would think of:
Stream<Chara...
What is the javascript MIME type for the type attribute of a script tag? [duplicate]
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This is a common mistake. The MIME type for javascript wasn't standardized for years. It's now officially: "application/javascript".
The real kicker here is that most browsers won't use that attribute anyway, at least not in the case of the script tag. They actually peek inside the pac...
Why shouldn't I use PyPy over CPython if PyPy is 6.3 times faster?
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NOTE: PyPy is more mature and better supported now than it was in 2013, when this question was asked. Avoid drawing conclusions from out-of-date information.
PyPy, as others have been quick to mention, has tenuous support for C extensions. It has...
In OS X Lion, LANG is not set to UTF-8, how to fix it?
I try to setup postgress in OS X Lion, and find that is not correctly setup the LOCALE environment var.
5 Answers
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Should I instantiate instance variables on declaration or in the constructor?
...he compiler.
The first variant is more readable.
You can't have exception handling with the first variant.
There is additionally the initialization block, which is as well put in the constructor(s) by the compiler:
{
a = new A();
}
Check Sun's explanation and advice
From this tutorial:
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How to remove unreferenced blobs from my git repo
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... and without further ado, may I present to you this useful command, "git-gc-all", guaranteed to remove all your git garbage until they might come up extra config variables:
git -c gc.reflogExpire=0 -c gc.reflogExpireUnreachab...
What causes a java.lang.ArrayIndexOutOfBoundsException and how do I prevent it?
What does ArrayIndexOutOfBoundsException mean and how do I get rid of it?
25 Answers
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Using ls to list directories and their total sizes
... it possible to use ls in Unix to list the total size of a sub-directory and all its contents as opposed to the usual 4K that (I assume) is just the directory file itself?
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