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Global and local variables in R
I am a newbie for R, and I am quite confused with the usage of local and global variables in R.
3 Answers
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Do you (really) write exception safe code? [closed]
Exception handling (EH) seems to be the current standard, and by searching the web, I can not find any novel ideas or methods that try to improve or replace it (well, some variations exist, but nothing novel).
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Elegant ways to support equivalence (“equality”) in Python classes
...om classes it is often important to allow equivalence by means of the == and != operators. In Python, this is made possible by implementing the __eq__ and __ne__ special methods, respectively. The easiest way I've found to do this is the following method:
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Upload failed You need to use a different version code for your APK because you already have one wit
...lay's Developer Console? I have just changed the version code from 2 to 3 and it failed to upload the build.
19 Answers
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How do I select a merge strategy for a git rebase?
...xtra options that are understood by the chosen merge strategy.
NB: "Ours" and "theirs" mean the opposite of what they do during a straight merge. In other words, "theirs" favors the commits on the current branch.
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How do you remove a specific revision in the git history?
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To combine revision 3 and 4 into a single revision, you can use git rebase. If you want to remove the changes in revision 3, you need to use the edit command in the interactive rebase mode. If you want to combine the changes into a single revision...
In Javascript, how to conditionally add a member to an object?
... b: conditionB ? 5 : undefined,
c: conditionC ? 5 : undefined,
// and so on...
});
And obtain the results you expect (if conditionB is false, then b will not exist in a).
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In C/C++ what's the simplest way to reverse the order of bits in a byte?
...e, I'm curious as to what is the "simplest" for a developer to implement. And by reversing I mean:
35 Answers
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What's a concise way to check that environment variables are set in a Unix shell script?
...(an empty string) is OK — not exactly what you want, but the alternative and older notation.
The second variant (using :?) requires DEST to be set and non-empty.
If you supply no message, the shell provides a default message.
The ${var?} construct is portable back to Version 7 UNIX and the Bourne ...
What's the cleanest way of applying map() to a dictionary in Swift?
...values. It also includes a filter(_:) overload which returns a Dictionary, and init(uniqueKeysWithValues:) and init(_:uniquingKeysWith:) initializers to create a Dictionary from an arbitrary sequence of tuples. That means that, if you want to change both the keys and values, you can say something li...