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Applying a function to every row of a table using dplyr?
...utate(ab =Coalesce(a,b))
Note that implementing the vectorization in C / C++ will be faster, but there isn't a magicPony package that will write the function for you.
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File name? Path name? Base name? Naming standard for pieces of a path
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In C++, Boost.Filesystem has devised a nomenclature for the various parts of a path. See the path decomposition reference documentation for details, as well as this tutorial.
Here's a summary based on the tutorial. For:
Windo...
What is the __del__ method, How to call it?
...k?
Here is a slightly opinionated answer.
Don't use __del__. This is not C++ or a language built for destructors. The __del__ method really should be gone in Python 3.x, though I'm sure someone will find a use case that makes sense. If you need to use __del__, be aware of the basic limitations per...
Measure time in Linux - time vs clock vs getrusage vs clock_gettime vs gettimeofday vs timespec_get?
...blem is that there are several different time functions available in C and C++, and some of them vary in behavior between implementations. There are also a lot of half-answers floating around. Compiling a list of clock functions together with their properties would answer the question properly. F...
What is the JUnit XML format specification that Hudson supports?
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I found a way around it. Since we are using c++ I am just reporting the number of failures in the failure message and using the "Stack Trace" to report the actual failures. Since the stack trace is reported from the text withing the body of the failure element, new lin...
Stack smashing detected
...t other memory problems such as memory leaks: How to find memory leak in a C++ code/project?
Valgrind SGCheck
As mentioned by others, Valgrind is not good at solving this kind of problem.
It does have an experimental tool called SGCheck:
SGCheck is a tool for finding overruns of stack and glo...
Using smart pointers for class members
...ving trouble understanding the usage of smart pointers as class members in C++11. I have read a lot about smart pointers and I think I do understand how unique_ptr and shared_ptr / weak_ptr work in general. What I don't understand is the real usage. It seems like everybody recommends using uniq...
What are good examples of genetic algorithms/genetic programming solutions? [closed]
...everything in their power to hurt the competition.
Edit:
I wrote it in C++ using no frameworks. Wrote my own neural net and GA code. Eric, thank you for saying it is plausible. People usually don't believe in the powers of GA (although the limitations are obvious) until they played with it. GA i...
How to use base class's constructors and assignment operator in C++?
... @CravingSpirit they are used in different situations, this is basic C++ I suggest you read a bit more about it.
– Motti
Jul 14 '13 at 12:53
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Lock, mutex, semaphore… what's the difference?
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Here's a quick tour noting how some languages answer these details.
C, C++ (pthreads)
A mutex is implemented via pthread_mutex_t. By default, they can't be shared with any other processes (PTHREAD_PROCESS_PRIVATE), however mutex's have an attribute called pshared. When set, so the mutex is sha...