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Python loop that also accesses previous and next values

... The edited version of this is still not logically sound: At the end of the loop obj and next_ will be the same object for the last iteration, which may have unintended side effects. – TemporalWolf Dec 5 '17 at 22:01 ...
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Getting the caller function name inside another function in Python? [duplicate]

...on 2 each frame record is a list. The third element in each record is the caller name. What you want is this: >>> import inspect >>> def f(): ... print inspect.stack()[1][3] ... >>> def g(): ... f() ... >>> g() g For Python 3.5+, each frame record i...
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Why rename synthesized properties in iOS with leading underscores? [duplicate]

...s is an artifact of a previous version of the Objective-C runtime. Originally, @synthesize was used to create accessors methods, but the runtime still required that instance variables had to be instantiated explicitly: @interface Foo : Bar { Baz *_qux; } @property (retain) Baz *qux; @end @imp...
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What is the difference between “long”, “long long”, “long int”, and “long long int” in C++?

...es <limits.h> are applicable. In terms of long double, that's actually a floating point value rather than an integer. Similarly to the integral types, it's required to have at least as much precision as a double and to provide a superset of values over that type (meaning at least those valu...
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Unix - create path of folders and file

...her/path/here && touch $_/cpredthing.txt. The $_ expands to essentially the "last argument in the last command executed". – Sgnl Apr 19 '16 at 1:37 4 ...
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How do I import the Django DoesNotExist exception?

...y of the model itself, in this case Answer. Your problem is that you are calling the get method - which raises the exception - before it is passed to assertRaises. You need to separate the arguments from the callable, as described in the unittest documentation: self.assertRaises(Answer.DoesNotExis...
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Importing from a relative path in Python

...his method is still commonly used in some situations, where you aren't actually ever 'installing' your package. For example, it's popular with Django users. You can add Common/ to your sys.path (the list of paths python looks at to import things): import sys, os sys.path.append(os.path.join(os.p...
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Can a pointer to base point to an array of derived objects?

...= 0; i < 10; ++i) shapes[i]->draw(); } Note that you have to do an extra step of initializing the Rectangle, since initializing the array only sets up the pointers, and not the objects themselves. share | ...
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Pandas aggregate count distinct

... Just adding to the answers already given, the solution using the string "nunique" seems much faster, tested here on ~21M rows dataframe, then grouped to ~2M %time _=g.agg({"id": lambda x: x.nunique()}) CPU times: user 3min 3s, sys: 2.94 s, total: 3min 6s Wall time: 3min 20s %time _=g.ag...
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JComboBox Selection Change Listener?

...x(); -or- Object selectedObject = myComboBox.getSelectedItem(); -or- String selectedValue = myComboBox.getSelectedValue().toString(); share | improve this answer | fol...