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Checking for empty queryset in Django
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@Wtower The code you refer to has for contract to raise 404 if the filtering expression does not hit any records or to produce a list of the result if there are records. The code there will hit the database just once. If they used exist() or count() to first check whether there ar...
I need to generate uuid for my rails application. What are the options(gems) I have? [duplicate]
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When should I use ugettext_lazy?
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edited Aug 5 '19 at 10:24
rktavi
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answered Nov 12 '10 at 12:37
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What is setup.py?
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setup.py is a python file, which usually tells you that the module/package you are about to ins...
pandas dataframe columns scaling with sklearn
...gt;> scaler = MinMaxScaler()
>>> dfTest = pd.DataFrame({'A':[14.00,90.20,90.95,96.27,91.21],
'B':[103.02,107.26,110.35,114.23,114.68],
'C':['big','small','big','small','small']})
>>> dfTest[['A', 'B']] = scaler.fit_transfor...
What is a higher kinded type in Scala?
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answered Jun 21 '11 at 14:49
Adriaan MoorsAdriaan Moors
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What's the difference between SortedList and SortedDictionary?
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– Daniel Imms
Feb 23 '13 at 5:54
I think the Sorteddictionary is an AVL-tree or Red-Blacktree( all operation cost...
When to use NSInteger vs. int
...possible integer type, which on 32 bit systems is just an int, while on a 64-bit system it's a long.
I'd stick with using NSInteger instead of int/long unless you specifically require them.
NSInteger/NSUInteger are defined as *dynamic typedef*s to one of these types, and they are defined like thi...
Python exit commands - why so many and when should each be used?
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How to update PATH variable permanently from Windows command line?
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The documentation on how to do this can be found on MSDN. The key extract is this:
To progr...