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How do I pass command-line arguments to a WinForms application?
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edited May 23 '16 at 8:45
answered Jul 24 '09 at 19:02
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Format an Integer using Java String Format
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3 Answers
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postgresql COUNT(DISTINCT …) very slow
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323
You can use this:
SELECT COUNT(*) FROM (SELECT DISTINCT column_name FROM table_name) AS temp;...
How to assign colors to categorical variables in ggplot2 that have stable mapping?
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edited Apr 3 '16 at 16:20
Axeman
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Why is this F# code so slow?
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The problem is that the min3 function is compiled as a generic function that uses generic comparison (I thought this uses just IComparable, but it is actually more complicated - it would use structural comparison for F# types and it's fairly complex lo...
How to get first element in a list of tuples?
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>>> a = [(1, u'abc'), (2, u'def')]
>>> [i[0] for i in a]
[1, 2]
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How to calculate time in hours between two dates in iOS
...weenDates = [date1 timeIntervalSinceDate:date2];
double secondsInAnHour = 3600;
NSInteger hoursBetweenDates = distanceBetweenDates / secondsInAnHour;
See, the apple reference library http://developer.apple.com/library/mac/navigation/
or if you are using Xcode just select help/documentation from ...
How to find the size of an array in postgresql
...in a single or multidimensional array. So select cardinality(ARRAY[[1,2], [3,4]]); would return 4, whereas select array_length(ARRAY[[1,2], [3,4]], 1) would return 2. If you're counting the first dimension, array_length is a safer bet.
– Roshambo
Sep 20 '17 at ...