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How to remove a key from Hash and get the remaining hash in Ruby/Rails?
... your five-minutes-of-editing are up, you can always copy, delete, modify, and repost a comment.
– iconoclast
May 13 at 23:17
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Difference between Big-O and Little-O Notation
What is the difference between Big-O notation O(n) and Little-O notation o(n) ?
4 Answers
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Dynamically select data frame columns using $ and a character value
I have a vector of different column names and I want to be able to loop over each of them to extract that column from a data.frame. For example, consider the data set mtcars and some variable names stored in a character vector cols . When I try to select a variable from mtcars using a dynamic s...
How to convert byte array to string and vice versa?
I have to convert a byte array to string in Android, but my byte array contains negative values.
22 Answers
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What is the difference between _tmain() and main() in C++?
...n does.
_tmain is a Microsoft extension.
main is, according to the C++ standard, the program's entry point.
It has one of these two signatures:
int main();
int main(int argc, char* argv[]);
Microsoft has added a wmain which replaces the second signature with this:
int wmain(int argc, wchar_t* ...
Reorder levels of a factor without changing order of values
I have data frame with some numerical variables and some categorical factor variables. The order of levels for those factors is not the way I want them to be.
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Linux error while loading shared libraries: cannot open shared object file: No such file or director
... no libpthread_rt.so.1 in that listing. You probably need to re-configure and re-build it so that it depends on the library you have, or install whatever provides libpthread_rt.so.1.
Generally, the numbers after the .so are version numbers, and you'll often find that they are symlinks to each othe...
Does anyone still use [goto] in C# and if so why? [closed]
I was wondering whether anyone still uses the "goto" keyword syntax in C# and what possible reasons there are for doing so.
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What is a Y-combinator? [closed]
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@Andre MacFie: I didn't comment on the effort, I commented on the quality. In general, the policy on Stack Overflow is that answers should be self contained, with links to more information.
– Jørgen Fogh...
Mutex example / tutorial? [closed]
I'm new to multithreading, and was trying to understand how mutexes work. Did a lot of Googling but it still left some doubts of how it works because I created my own program in which locking didn't work.
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