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What's the fastest way to merge/join data.frames in R?
For example (not sure if most representative example though):
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What's the most efficient test of whether a PHP string ends with another string?
The standard PHP way to test whether a string $str ends with a substring $test is:
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Standard deviation of a list
I want to find mean and standard deviation of 1st, 2nd,... digits of several (Z) lists. For example, I have
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What does “not run” mean in R help pages?
Sometimes on an R help page the phrase "not run" appears in comments. Check out this from the help page for "with()":
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Repairing Postgresql after upgrading to OSX 10.7 Lion
I recently upgraded to OSX 10.7, at which point my rails installation completely borked when trying to connect to the psql server. When I do it from the command line using
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Scala 2.8 breakOut
In Scala 2.8 , there is an object in scala.collection.package.scala :
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When should we use intern method of String on String literals
According to String#intern() , intern method is supposed to return the String from the String pool if the String is found in String pool, otherwise a new string object will be added in String pool and the reference of this String is returned.
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Section vs Article HTML5
I have a page made up of various "sections" like videos, a newsfeed etc.. I am a bit confused how to represent these with HTML5. Currently I have them as HTML5 <section> s, but on further inspection it looks they the more correct tag would be <article> . Could anyone shed some light on...