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Speed up the loop operation in R
... over a data.frame object. It simply adds a new column to a data.frame and accumulates something. (simple operation). The data.frame has roughly 850K rows. My PC is still working (about 10h now) and I have no idea about the runtime.
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What is the difference between Raising Exceptions vs Throwing Exceptions in Ruby?
Ruby has two different exceptions mechanisms: Throw/Catch and Raise/Rescue.
3 Answers
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Hidden features of C
I know there is a standard behind all C compiler implementations, so there should be no hidden features. Despite that, I am sure all C developers have hidden/secret tricks they use all the time.
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jQuery vs jQuery Mobile vs jQuery UI?
I'm new to web development and there are just too many j* stuff out there. I wonder what are the differences between these frameworks?
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What is the difference between “AS” and “IS” in an Oracle stored procedure?
I see Oracle procedures sometimes written with "AS", and sometimes with "IS" keyword.
6 Answers
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Difference between Destroy and Delete
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ActiveRecord::Persistence.delete
Deletes the record in the database and freezes this instance to reflect that no changes should be made (since they can't be persisted). Returns the frozen instance.
The row is simply removed with an SQL DELETE statement on the record's primary key, and no...
Record file copy operation with Git
...a file in git using git-mv the status shows that the file has been renamed and even if I alter some portions it still considers to be almost the same thing (which is good because it lets me follow the history of it).
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Get decimal portion of a number with JavaScript
I have float numbers like 3.2 and 1.6 .
22 Answers
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Git reset --hard and push to remote repository
I had a repository that had some bad commits on it (D, E and F for this example).
5 Answers
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jQuery get textarea text
Recently I have started playing with jQuery, and have been following a couple of tutorials. Now I feel slightly competent with using it (it's pretty easy), and I thought it would be cool if I were able to make a 'console' on my webpage (as in, you press the ` key like you do in FPS games, etc.), a...