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How to join (merge) data frames (inner, outer, left, right)
...nner join: merge(df1, df2) will work for these examples because R automatically joins the frames by common variable names, but you would most likely want to specify merge(df1, df2, by = "CustomerId") to make sure that you were matching on only the fields you desired. You can also use the by.x and b...
An efficient compression algorithm for short text strings [closed]
I'm searching for an algorithm to compress small text strings: 50-1000 bytes (i.e. URLs). Which algorithm works best for this?
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What is a reasonable code coverage % for unit tests (and why)? [closed]
...and she knows those
factors better than I do – it’s her
code after all. There is no single,
simple, answer, and she’s smart enough
to handle the truth and work with
that.”
“I see,” said the young apprentice,
“but if there is no single simple
answer, then why did you ...
How can I get all constants of a type by reflection?
How can I get all constants of any type using reflection?
4 Answers
4
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What is the reason not to use select *?
I've seen a number of people claim that you should specifically name each column you want in your select query.
20 Answers
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Capybara Ambiguity Resolution
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Specifically, Capybara 2.0 has intelligent waiting logic to ensure specs pass or fail consistently across machines of differing processing speeds while only waiting the minimum necessary time. Using first as suggested above, unless y...
How can I find all of the distinct file extensions in a folder hierarchy?
...inux machine I would like to traverse a folder hierarchy and get a list of all of the distinct file extensions within it.
1...
C state-machine design [closed]
I am crafting a small project in mixed C and C++. I am building one small-ish state-machine at the heart of one of my worker thread.
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Where can I locate themes for VS2012
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New Theme editor Specifically for 2012:
http://visualstudiogallery.msdn.microsoft.com/366ad100-0003-4c9a-81a8-337d4e7ace05
Comes w/ VS 2010 style blue and a few others...
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When should I use jQuery's document.ready function?
...document.ready when I first started to use Javascript/jQuery but I never really learned why.
8 Answers
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