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MySQL get the date n days ago as a timestamp
In MySQL, how would I get a timestamp from, say 30 days ago?
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Passing multiple error classes to ruby's rescue clause in a DRY fashion
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Add a number to each selection in Sublime Text 2, incremented once per selection
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Failed to build gem native extension (installing Compass)
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Retrieve only the queried element in an object array in MongoDB collection
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db.test.find({"shapes.color": "red"}, {_id: 0, 'shapes.$': 1});
MongoDB 3.2 Update
Starting with the 3.2 release, you can use the new $filter aggregation operator to filter an array during projection, which has the benefit of including all matches, instead of just the first one.
db.test.aggrega...
Difference between “git checkout ” and “git checkout -- ”
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edited Sep 8 '16 at 13:47
answered Jul 3 '11 at 4:51
z...
Set width of a “Position: fixed” div relative to parent div
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answered May 3 '11 at 19:02
jeroenjeroen
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Set value for particular cell in pandas DataFrame using index
...y df.
In [18]: %timeit df.set_value('C', 'x', 10)
100000 loops, best of 3: 2.9 µs per loop
In [20]: %timeit df['x']['C'] = 10
100000 loops, best of 3: 6.31 µs per loop
In [81]: %timeit df.at['C', 'x'] = 10
100000 loops, best of 3: 9.2 µs per loop
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Is std::vector so much slower than plain arrays?
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Using the following:
g++ -O3 Time.cpp -I <MyBoost>
./a.out
UseArray completed in 2.196 seconds
UseVector completed in 4.412 seconds
UseVectorPushBack completed in 8.017 seconds
The whole thing completed in 14.626 seconds
So array is...