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Group by multiple columns in dplyr, using string vector input
I'm trying to transfer my understanding of plyr into dplyr, but I can't figure out how to group by multiple columns.
9 Answ...
Include constant in string without concatenating
Is there a way in PHP to include a constant in a string without concatenating?
12 Answers
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Rich vs Anemic Domain Model [closed]
I am deciding if I should use a Rich Domain Model over an Anemic Domain Model, and looking for good examples of the two.
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Significance of a .inl file in C++
What are the advantages of having declarations in a .inl file? When would I need to use the same?
5 Answers
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Can you use a trailing comma in a JSON object?
When manually generating a JSON object or array, it's often easier to leave a trailing comma on the last item in the object or array. For example, code to output from an array of strings might look like (in a C++ like pseudocode):
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How to raise a ValueError?
I have this code which finds the largest index of a specific character in a string, however I would like it to raise a ValueError when the specified character does not occur in a string.
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What are the best use cases for Akka framework [closed]
I have heard lots of raving about Akka framework (Java/Scala service platform), but so far have not seen many actual examples of use cases it would be good for. So I would be interested in hearing about things developers have used it succesfully.
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In a Bash script, how can I exit the entire script if a certain condition occurs?
I'm writing a script in Bash to test some code. However, it seems silly to run the tests if compiling the code fails in the first place, in which case I'll just abort the tests.
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Causes of getting a java.lang.VerifyError
I'm investigating the following java.lang.VerifyError
25 Answers
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Python element-wise tuple operations like sum
Is there anyway to get tuple operations in Python to work like this:
12 Answers
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