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detach all packages while working in R
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So, someone should have simply answered the following.
lapply(paste('package:',names(sessionInfo()$otherPkgs),sep=""),detach,character.only=TRUE,unload=TRUE)
(edit: 6-28-19)
In the latest version of R 3.6.0 please use instead.
invis...
JS: iterating over result of getElementsByClassName using Array.forEach
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You linked the wrong benchmark. Here is the correct one measurethat.net/Benchmarks/Show/4076/0/… Just ran it on my low-end phone, got 160k/s vs 380k/s. Since you mentioned DOM manipulation, here is that too measurethat.net/Benchmarks/Show/5705/0/… Got 50k/s vs 130k/s. As y...
Why does sun.misc.Unsafe exist, and how can it be used in the real world?
...ts and then interpret the constructor invocation as any other method call.
One can track the data from the native address.It is possible to retrieve an
object’s memory address using the java.lang.Unsafe class, and operate on its fields directly via unsafe get/put methods!
Compile time optimization...
Explanation of JSONB introduced by PostgreSQL
...ONB and it's already trending on hacker news . It would be great if someone could explain how it's different from Hstore and JSON previously present in PostgreSQL. What are its advantages and limitations and when should someone consider using it?
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What is the difference between DSA and RSA?
...ryption algorithms that require public and private keys. Why would I pick one versus the other to provide encryption in my client server application?
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Why are static variables considered evil?
...t given a choice between two otherwise equally valid designs, the testable one is superior. Being testable certainly doesn't equate to being well designed, but I've rarely come across untestable good designs, and I think they're sufficiently rare that I have no problem in making testability a genera...
What is Java String interning?
...ist of names where 'john' appears 1000 times, by interning you ensure only one 'john' is actually allocated memory.
This can be useful to reduce memory requirements of your program. But be aware that the cache is maintained by JVM in permanent memory pool which is usually limited in size compared t...
Unable to update the EntitySet - because it has a DefiningQuery and no element exis
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It usually happens because one of the following reasons:
Entity Set is mapped from Database view
A custom Database query
Database table doesn't have a primary key
After doing so, you may still need to update in the Entity Framework designer (or alt...
Which C++ idioms are deprecated in C++11?
...due to first-class support for rvalue references.
Safe bool: This was mentioned earlier. Explicit operators of C++11 obviate this very common C++03 idiom.
Shrink-to-fit: Many C++11 STL containers provide a shrink_to_fit() member function, which should eliminate the need swapping with a temporary.
Te...
Why is it impossible to build a compiler that can determine if a C++ function will change the value
...ven program will terminate. This is known as the halting problem, and it's one of those things that's not computable.
To be clear, you can write a compiler that can determine that a function does change the variable in some cases, but you can't write one that reliably tells you that the function wi...