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Where can I learn how to write C code to speed up slow R functions? [closed]
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Well there is the good old Use the source, Luke! --- R itself has plenty of (very efficient) C code one can study, and CRAN has hundreds of packages, some from authors you trust. That provides real, tested examples to study and adapt.
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How can I use map and receive an index as well in Scala?
Is there any List/Sequence built-in that behaves like map and provides the element's index as well?
8 Answers
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vector::at vs. vector::operator[]
I know that at() is slower than [] because of its boundary checking, which is also discussed in similar questions like C++ Vector at/[] operator speed or ::std::vector::at() vs operator[] << surprising results!! 5 to 10 times slower/faster! . I just don't understand what the at() met...
Does it make sense to use “as” instead of a cast even if there is no null check? [closed]
...de examples and (recently) even a book, I keep stumbling about code like this:
13 Answers
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What's the simplest way to test whether a number is a power of 2 in C++?
I need a function like this:
17 Answers
17
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Strengths of Shell Scripting compared to Python [closed]
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Shell scripting has simpler notations for I/O redirection.
It is simpler to create pipelines out of existing programs in shell.
Shell scripting reuses entire programs.
Shell is universally available (on anything like Unix) - Python is not necessarily installed.
'Tis true that you can ...
Quickly create a large file on a Linux system
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dd from the other answers is a good solution, but it is slow for this purpose. In Linux (and other POSIX systems), we have fallocate, which uses the desired space without having to actually writing to it, works with most modern disk based file systems...
Measuring text height to be drawn on Canvas ( Android )
...aight forward way to measure the height of text?
The way I am doing it now is by using Paint's measureText() to get the width, then by trial and error finding a value to get an approximate height. I've also been messing around with FontMetrics , but all these seem like approximate methods that su...
In laymans terms, what does 'static' mean in Java? [duplicate]
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static means that the variable or method marked as such is available at the class level. In other words, you don't need to create an instance of the class to access it.
public class Foo {
public static void doStuff(){
// does stuff
}
}
So, instead of creating an...
STL or Qt containers?
...fers much more complete functionality compared to std::basic_string and it is
completely Unicode aware. It also offers an efficient COW implementation, which I've come to rely on heavily.
Qt's containers:
offer the same COW implementation as in QString, which is extremely useful when it comes to...