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Why are arrays covariant but generics are invariant?
...possible to call these functions on an array of exactly the type Object[]. One could not, for example, shuffle an array of strings.
Therefore, both Java and C# treat array types covariantly. For instance, in C# string[] is a subtype of object[], and in Java String[] is a subtype of Object[].
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ruby inheritance vs mixins
In Ruby, since you can include multiple mixins but only extend one class, it seems like mixins would be preferred over inheritance.
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Is the Scala 2.8 collections library a case of “the longest suicide note in history”? [closed]
... Update: The final Scala 2.8 release has a mechanism like the one I described. If you look up BitSet in the scaladocs you find: def map [B] (f: (Int) ⇒ B) : BitSet[B] [use case] Builds a new collection by applying a function to all elements of this bitset.
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Error: Cannot access file bin/Debug/… because it is being used by another process
...on, that the problem seems to only crop up when you build the project with one of the designers open. So, the solution that has worked for me long term and prevented me from ever dealing with one of those silly errors again is making sure that I always close all designer windows before building a Wi...
Drop rows with all zeros in pandas data frame
... Just a note: OP wanted to drop rows with all columns having value 0, but one can infer all method.
– paulochf
Apr 25 '16 at 20:02
1
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How do I check out a remote Git branch?
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With One Remote
Jakub's answer actually improves on this. With Git versions ≥ 1.6.6, with only one remote, you can just do:
git fetch
git checkout test
As user masukomi points out in a comment, git checkout test will NOT work i...
Split column at delimiter in data frame [duplicate]
I would like to split one column into two within at data frame based on a delimiter. For example,
6 Answers
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omp parallel vs. omp parallel for
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I don't think there is any difference, one is a shortcut for the other. Although your exact implementation might deal with them differently.
The combined parallel worksharing constructs are a shortcut for
specifying a parallel construct containing one works...
Is recursion a feature in and of itself?
...eature" he hadn't taught yet, that was wrong.
Reading between the lines, one possibility is that by using recursion, you avoided ever using a feature that was supposed to be a learning outcome for his course. For example, maybe you didn't use iteration at all, or maybe you only used for loops inst...
Creating a DateTime in a specific Time Zone in c#
I'm trying to create a unit test to test the case for when the timezone changes on a machine because it has been incorrectly set and then corrected.
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