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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
87.4k2020 gold badges106106 silver badges128128 bronze badges
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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...
Forced naming of parameters in Python
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223
In Python 3 - Yes, you can specify * in the argument list.
From docs:
Parameters after “*...
Design for Facebook authentication in an iOS app that also accesses a secured web service
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n00bProgrammer
4,04133 gold badges2626 silver badges5858 bronze badges
answered Jan 7 '11 at 13:40
Dan RayDan Ray
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How to detect the currently pressed key?
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163
if ((Control.ModifierKeys & Keys.Shift) != 0)
This will also be true if Ctrl+Shift is dow...