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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...
Not class selector in jQuery
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answered Jan 6 '11 at 10:53
lonesomedaylonesomeday
207k4545 gold badges296296 silver badges306306 bronze badges
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reference assignment is atomic so why is Interlocked.Exchange(ref Object, Object) needed?
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answered Feb 3 '10 at 16:20
Eric LippertEric Lippert
599k164164 gold badges11551155 silver badges20142014 bronze badges
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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?
3 Answers
3
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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
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answered Jan 7 '11 at 13:40
Dan RayDan Ray
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Get list from pandas DataFrame column headers
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edited Apr 3 '19 at 9:51
cs95
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How do I base64 encode (decode) in C?
..., 'v',
'w', 'x', 'y', 'z', '0', '1', '2', '3',
'4', '5', '6', '7', '8', '9', '+', '/'};
static char *decoding_table = NULL;
static int mod_table[] = {0, 2, 1};
char *base64_encode(const unsigned char *data,
size_t ...
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...