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dplyr: “Error in n(): function should not be called directly”
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I presume you have dplyr and plyr loaded in the same session. dplyr is not plyr. ddply is not a function in the dplyr package.
Both dplyr and plyr have the functions summarise/summarize.
Look at the results of conflicts() to see masked objects.
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Should a “static final Logger” be declared in UPPER-CASE?
In Java, static final variables are constants and the convention is that they should be in upper-case. However, I have seen that most people declare loggers in lower-case which comes up as a violation in PMD .
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How can I get the behavior of GNU's readlink -f on a Mac?
...ption -f that follows additional links. This doesn't seem to work on Mac and possibly BSD based systems. What would the equivalent be?
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WPF Timer Like C# Timer
...ge of making the timer a Control.) If you don't you'll have a memory leak and possibly other bugs.
– Trade-Ideas Philip
Nov 28 '16 at 14:11
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How to properly stop the Thread in Java?
...t in the class scope.
When you wish to stop the thread, you set this flag and call join() on the thread and wait for it to finish.
Make sure that the flag is thread safe by using a volatile variable or by using getter and setter methods which are synchronised with the variable being used as the fl...
Case insensitive searching in Oracle
The default behaviour of LIKE and the other comparison operators, = etc is case-sensitive.
6 Answers
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std::back_inserter for a std::set?
...f an element is determined by the comparator of the set. Use std::inserter and pass it .begin():
std::set<int> s1, s2;
s1 = getAnExcitingSet();
transform(s1.begin(), s1.end(),
std::inserter(s2, s2.begin()), ExcitingUnaryFunctor());
The insert iterator will then call s2.insert(s2....
How to use LINQ to select object with minimum or maximum property value
... Probably a little slower than just implementing IComparable and using Min (or a for loop). But +1 for a O(n) linqy solution.
– Matthew Flaschen
May 27 '09 at 6:07
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Should have subtitle controller already set Mediaplayer error Android
...ying a music (or other source), it checks if there is a SubtitleController and shows this message if it's not set.
It doesn't seem to care about if the source you want to play is a music or video. Not sure why he did that.
Short answer: Don't care about this "Exception".
Edit :
Still present in...
Is main() really start of a C++ program?
The section $3.6.1/1 from the C++ Standard reads,
11 Answers
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