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Getting the class name of an instance?
...note that the above method works with new-style classes only (in Python 3+ all classes are "new-style" classes). Your code might use some old-style classes. The following works for both:
x.__class__.__name__
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Is there a range class in C++11 for use with range based for loops?
...:irange, which is a bit more focused in scope.
C++20's range library will allow you to do this via view::iota(start, end).
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How to efficiently compare two unordered lists (not sets) in Python?
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For short lists, big-O analysis is usually irrelevant because the timings are dominated by constant factors. For the longer lists, I suspect something is wrong with your benchmarking. For 100 ints with 5 repeats each, I get: 127 usec for sorted and 42 for Count...
How do I check if there are duplicates in a flat list?
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Use set() to remove duplicates if all values are hashable:
>>> your_list = ['one', 'two', 'one']
>>> len(your_list) != len(set(your_list))
True
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Running a specific test case in Django when your app has a tests directory
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Checkout django-nose. It allows you to specify tests to run like:
python manage.py test another.test:TestCase.test_method
or as noted in comments, use the syntax:
python manage.py test another.test.TestCase.test_method
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Disable a method in a ViewSet, django-rest-framework
...ethods but I did not able to find out how to disable the PATCH method specially if you are using routers.
– Muneeb Ahmad
Mar 31 '15 at 14:56
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Rounding up to next power of 2
...mon: it's the portable solution. There's no common efficient algorithm for all architectures
– phuclv
Dec 6 '13 at 9:27
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String concatenation: concat() vs “+” operator
...then throwing it away when you create the final String. In practice memory allocation is surprisingly fast.
Update: As Pawel Adamski notes, performance has changed in more recent HotSpot. javac still produces exactly the same code, but the bytecode compiler cheats. Simple testing entirely fails bec...
How do I use IValidatableObject?
... Prop1 = 1,
Prop2 = 2
};
bool validateAllProperties = false;
var results = new List<ValidationResult>();
bool isValid = Validator.TryValidateObject(
toValidate,
new ValidationContext(toValidate, null, null),
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How do you calculate the average of a set of circular data? [closed]
... sum_i_from_1_to_N cos(a[i])
The method given by starblue is computationally equivalent, but his reasons are clearer and probably programmatically more efficient, and also work well in the zero case, so kudos to him.
The subject is now explored in more detail on Wikipedia, and with other uses, l...