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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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Objective-C: difference between id and void *
What is the difference between id and void * ?
7 Answers
7
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What is external linkage and internal linkage?
I want to understand the external linkage and internal linkage and their difference.
9 Answers
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Difference between case object and object
Is there any difference between case object and object in scala?
7 Answers
7
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Can an abstract class have a constructor?
Can an abstract class have a constructor?
22 Answers
22
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When to use dynamic vs. static libraries
When creating a class library in C++, you can choose between dynamic ( .dll , .so ) and static ( .lib , .a ) libraries. What is the difference between them and when is it appropriate to use which?
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In Clojure, when should I use a vector over a list, and the other way around?
I read that Vectors are not seqs, but Lists are. I'm not sure what the rationale is for using one over the other. It seems that vectors are used the most, but is there a reason for that?
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Is storing a delimited list in a database column really that bad?
Imagine a web form with a set of check boxes (any or all of them can be selected). I chose to save them in a comma separated list of values stored in one column of the database table.
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Alternate FizzBuzz Questions [closed]
Anybody have any good FizzBuzz type questions that are not the FizzBuzz problem?
14 Answers
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C++ project organisation (with gtest, cmake and doxygen)
I am new to programming in general so I decided that I would start by making a simple vector class in C++. However I would like to get in to good habits from the start rather than trying to modify my workflow later on.
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