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Inherit docstrings in Python class inheritance
...'d like each class and inherited class to have good docstrings. So I think for the inherited class, I'd like it to:
5 Answe...
what does the __file__ variable mean/do?
... usually just hard-wire these with the actual path. But there is a reason for these statements that determine path at runtime, and I would really like to understand the os.path module so that I can start using it.
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Print all properties of a Python Class [duplicate]
...t'}
# now dump this in some way or another
print(', '.join("%s: %s" % item for item in attrs.items()))
If you want to store Python objects on the disk you should look at shelve — Python object persistence.
share
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How to initialize all members of an array to the same value?
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C99 has a lot of nice features for structure and array initialization; the one feature it does not have (but Fortran IV, 1966, had) is a way to repeat a particular initializer for an array.
– Jonathan Leffler
Oct 14 '...
Is it ever advantageous to use 'goto' in a language that supports loops and functions? If so, why?
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There are a few reasons for using the "goto" statement that I'm aware of (some have spoken to this already):
Cleanly exiting a function
Often in a function, you may allocate resources and need to exit in multiple places. Programmers can simplify ...
correct way to use super (argument passing)
... super(E, self).__init__(arg, *args, **kwargs)
print "MRO:", [x.__name__ for x in E.__mro__]
E(10)
yields
MRO: ['E', 'C', 'A', 'D', 'B', 'Base', 'object']
E arg= 10
C arg= 10
A
D arg= 10
B
Note that for this to work, Base must be the penultimate class in the MRO.
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Pandas selecting by label sometimes return Series, sometimes returns DataFrame
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You have an index with three index items 3. For this reason df.loc[3] will return a dataframe.
The reason is that you don't specify the column. So df.loc[3] selects three items of all columns (which is column 0), while df.loc[3,0] will return a Series. E.g. df.loc[1:2...
Catching an exception while using a Python 'with' statement
To my shame, I can't figure out how to handle exception for python 'with' statement. If I have a code:
4 Answers
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remove None value from a list without removing the 0 value
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>>> L = [0, 23, 234, 89, None, 0, 35, 9]
>>> [x for x in L if x is not None]
[0, 23, 234, 89, 0, 35, 9]
Just for fun, here's how you can adapt filter to do this without using a lambda, (I wouldn't recommend this code - it's just for scientific purposes)
>>> fro...
Create a custom event in Java
...n("Hello!!");
// Notify everybody that may be interested.
for (HelloListener hl : listeners)
hl.someoneSaidHello();
}
}
// Someone interested in "Hello" events
class Responder implements HelloListener {
@Override
public void someoneSaidHello() {
Syst...