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Confusion between factor levels and factor labels
There seems to be a difference between levels and labels of a factor in R.
Up to now, I always thought that levels were the 'real' name of factor levels, and labels were the names used for output (such as tables and plots). Obviously, this is not the case, as the following example shows:
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Meaning of @classmethod and @staticmethod for beginner? [duplicate]
Could someone explain to me the meaning of @classmethod and @staticmethod in python? I need to know the difference and the meaning.
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Is there a better way to express nested namespaces in C++ within the header
I switched from C++ to Java and C# and think the usage of namespaces/packages is much better there (well structured). Then I came back to C++ and tried to use namespaces the same way but the required syntax is horrible within the header file.
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What exactly is an “open generic type” in .NET? [duplicate]
I was going through Asp.Net MVC lesson and learned that, for a method to qualify as an action for a controller,
4 Answer...
Which SQL query is faster? Filter on Join criteria or Where clause?
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Performance-wise, they are the same (and produce the same plans)
Logically, you should make the operation that still has sense if you replace INNER JOIN with a LEFT JOIN.
In your very case this will look like this:
SELECT *
FROM TableA a
LEFT JOIN
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What is the JavaScript >>> operator and how do you use it?
I was looking at code from Mozilla that add a filter method to Array and it had a line of code that confused me.
7 Answers
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Storing time-series data, relational or non?
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Definitely Relational. Unlimited flexibility and expansion.
Two corrections, both in concept and application, followed by an elevation.
Correction
It is not "filtering out the un-needed data"; it is selecting only the needed data. Yes, of course, if you have an Ind...
What are the differences between a HashMap and a Hashtable in Java?
What are the differences between a HashMap and a Hashtable in Java?
35 Answers
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Best practice multi language website
... before. Right now, I feel like it's time to get to know the possibilities and create my own personal preference to use in my upcoming projects.
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Fastest way to check if a string matches a regexp in ruby?
... avoids object allocations performed by other methods such as Regexp#match and =~:
Regexp#match?
Added Regexp#match?, which executes a regexp match without creating a back reference object and changing $~ to reduce object allocation.
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