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Assign multiple columns using := in data.table, by group
...t(dim(get(objectName))),by=objectName]. Trouble is that as.list has call overhead and also copies the small vector. If efficiency is a problem as number of groups rises then please let us know.
– Matt Dowle
May 21 '14 at 11:49
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Difference between “git checkout ” and “git checkout -- ”
...his is not Git-specific, it's a general Unix command line convention. Normally you use it to clarify that an argument is a file name rather than an option, e.g.
rm -f # does nothing
rm -- -f # deletes a file named "-f"
git checkout1 also takes -- to mean that subsequent arguments are not ...
How to get result of console.trace() as string in javascript with chrome or firefox?
...don't define names for functions and I also can not get their names with callee.caller.name .
6 Answers
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Python dictionary: are keys() and values() always the same order?
...e always a 1-to-1 mapping (assuming the dictionary is not altered between calling the 2 methods).
8 Answers
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Converting integer to string in Python
... string is done with the builtin str() function, which basically calls the __str__() method of its parameter.
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Should switch statements always contain a default clause?
...e back), I was told that it's good practice to include a default clause in all switch statements. I recently remembered this advice but can't remember what the justification was. It sounds fairly odd to me now.
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Library not loaded: libmysqlclient.16.dylib error when trying to run 'rails server' on OS X 10.6 wit
...and that I used to make it work for me. This way you don't need to use install_name_tool every time you update your mysql
sudo ln -s /usr/local/mysql/lib/libmysqlclient.18.dylib /usr/lib/libmysqlclient.18.dylib
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How can I check which version of Angular I'm using?
... huge file for a license. Second, relying on license file/comment is not really a great choice since it may change by a minfier bug.
– Afshin Moazami
Dec 8 '15 at 15:23
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Correct way to define C++ namespace methods in .cpp file
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Calling #2 "wrong" is a huge exaggeration. By this logic, all symbol names are "wrong" because they can potentially hide other symbol names in other scopes.
– tenfour
Dec 30 '11 at 16:59
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How to filter SQL results in a has-many-through relation
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I was curious. And as we all know, curiosity has a reputation for killing cats.
So, which is the fastest way to skin a cat?
The precise cat-skinning environment for this test:
PostgreSQL 9.0 on Debian Squeeze with decent RAM and settings.
6.000 ...