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How do I make a list of data frames?
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This isn't related to your question, but you want to use = and not <- within the function call. If you use <-, you'll end up creating variables y1 and y2 in whatever environment you're working in:
d1 <- data.frame(y1 <- c(1, 2, 3), y2 <- c(4, 5, ...
Why does my application spend 24% of its life doing a null check?
I've got a performance critical binary decision tree, and I'd like to focus this question on a single line of code. The code for the binary tree iterator is below with the results from running performance analysis against it.
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How do you use bcrypt for hashing passwords in PHP?
Every now and then I hear the advice "Use bcrypt for storing passwords in PHP, bcrypt rules".
11 Answers
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Why should I use core.autocrlf=true in Git?
I have a Git repository that is accessed from both Windows and OS X, and that I know already contains some files with CRLF line-endings. As far as I can tell, there are two ways to deal with this:
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Best practices for circular shift (rotate) operations in C++
Left and right shift operators (>) are already available in C++.
However, I couldn't find out how I could perform circular shift or rotate operations.
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Best practices for reducing Garbage Collector activity in Javascript
... which has a main loop that is called 60 times per second. There seems to be a lot of garbage collection going on (based on the 'sawtooth' output from the Memory timeline in the Chrome dev tools) - and this often impacts the performance of the application.
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Efficiency of Java “Double Brace Initialization”?
In Hidden Features of Java the top answer mentions Double Brace Initialization , with a very enticing syntax:
15 Answe...
What is Mocking?
...hing made as an imitation.
Mocking is primarily used in unit testing. An object under test may
have dependencies on other (complex) objects. To isolate the behavior
of the object you want to replace the other objects by mocks that
simulate the behavior of the real objects. This is useful if the rea...
Default constructor vs. inline field initialization
What's the difference between a default constructor and just initializing an object's fields directly?
5 Answers
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how to listen to N channels? (dynamic select statement)
to start an endless loop of executing two goroutines, I can use the code below:
5 Answers
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