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What is the difference between require() and library()?
What is the difference between require() and library() ?
8 Answers
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Why does X[Y] join of data.tables not allow a full outer join, or a left join?
...f a philosophical question about data.table join syntax. I am finding more and more uses for data.tables, but still learning...
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What characters are allowed in an email address?
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See RFC 5322: Internet Message Format and, to a lesser extent, RFC 5321: Simple Mail Transfer Protocol.
RFC 822 also covers email addresses, but it deals mostly with its structure:
addr-spec = local-part "@" domain ; global address
local-part ...
How can I profile C++ code running on Linux?
... a profiler, use one of the suggested ones.
However, if you're in a hurry and you can manually interrupt your program under the debugger while it's being subjectively slow, there's a simple way to find performance problems.
Just halt it several times, and each time look at the call stack. If there...
Should I always use a parallel stream when possible?
With Java 8 and lambdas it's easy to iterate over collections as streams, and just as easy to use a parallel stream. Two examples from the docs , the second one using parallelStream:
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Why do people say that Ruby is slow? [closed]
I like Ruby on Rails and I use it for all my web development projects. A few years ago there was a lot of talk about Rails being a memory hog and about how it didn't scale very well but these suggestions were put to bed by Gregg Pollack here.
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What is the difference between Amazon S3 and Amazon EC2 instance?
I need to create a web application using php mysql and html. The no.of requests and data will be very high. I need Amazon server space.
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AWS: How to disable all services?
I was dorking around with AWS (and related services), hoping that I could stay in the Free Tier, like I do when I'm exploring Google App Engine.
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What is the advantage of using REST instead of non-REST HTTP?
...dy really agrees on what REST is. The wikipedia page is heavy on buzzwords and light on explanation. The discussion page is worth a skim just to see how much people disagree on this. As far as I can tell however, REST means this:
Instead of having randomly named setter and getter URLs and using GET...
What is the HMVC pattern?
...n instead of MVC as version 2.x does. The page about this in Kohana's docs and the one on wikipedia didn't really give me a clear idea.
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