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Remove duplicated rows
I have read a CSV file into an R data.frame. Some of the rows have the same element in one of the columns. I would like to remove rows that are duplicates in that column. For example:
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Where does mongodb stand in the CAP theorem?
Everywhere I look, I see that MongoDB is CP.
But when I dig in I see it is eventually consistent.
Is it CP when you use safe=true? If so, does that mean that when I write with safe=true, all replicas will be updated before getting the result?
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Legality of COW std::string implementation in C++11
It had been my understanding that copy-on-write is not a viable way to implement a conforming std::string in C++11, but when it came up in discussion recently I found myself unable to directly support that statement.
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When do you use Java's @Override annotation and why?
What are the best practices for using Java's @Override annotation and why?
27 Answers
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Using ThreadPool.QueueUserWorkItem in ASP.NET in a high traffic scenario
I've always been under the impression that using the ThreadPool for (let's say non-critical) short-lived background tasks was considered best practice, even in ASP.NET, but then I came across this article that seems to suggest otherwise - the argument being that you should leave the ThreadPool to ...
In where shall I use isset() and !empty()
I read somewhere that the isset() function treats an empty string as TRUE , therefore isset() is not an effective way to validate text inputs and text boxes from a HTML form.
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Why do I need to explicitly push a new branch?
I am new in git and I am practicing. I created a local branch but I saw that when I did git push my branch was not uploaded to the repository. I had to actually do: git push -u origin --all .
Why is this? Isn't a branch a new change to be pushed by default? Why do I need to run the second com...
Can an abstract class have a constructor?
Can an abstract class have a constructor?
22 Answers
22
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Is a Python list guaranteed to have its elements stay in the order they are inserted in?
If I have the following Python code
6 Answers
6
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Objective-C: difference between id and void *
What is the difference between id and void * ?
7 Answers
7
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