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Why does this iterative list-growing code give IndexError: list assignment index out of range?
...or l in i:
j.append(l)
Of course, you'd never do this in practice if all you wanted to do was to copy an existing list. You'd just do:
j = list(i)
Alternatively, if you wanted to use the Python list like an array in other languages, then you could pre-create a list with its elements set to ...
Why does Python use 'magic methods'?
...lable, an object implements a method, def __len__(self) , and then it is called when you write len(obj) .
7 Answers
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How to get only the last part of a path in Python?
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I initially thought rstrip('/') would be simpler but then quickly realised I'd have to use rstrip(os.path.sep), so obviously the use of normpath is justified.
– Erik Kaplun
Jun 29 '14 at 13:44
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Android: How to enable/disable option menu item on button click?
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Anyway, the documentation covers all the things.
Changing menu items at runtime
Once the activity is created, the
onCreateOptionsMenu() method is called
only once, as described above. The
system keeps and re-uses the Menu you
define in this meth...
Shell one liner to prepend to a file
...t it sorta worked but weird things could happen, or it just didn't work at all, so it was furiously downvoted for a time. Such fun.
The solution exploits the exact implementation of file descriptors on your system and, because implementation varies significantly between nixes, it's success is enti...
A simple explanation of Naive Bayes Classification
... & part two being the confusion surrounding Training set.
In general all of Machine Learning Algorithms need to be trained for supervised learning tasks like classification, prediction etc. or for unsupervised learning tasks like clustering.
During the training step, the algorithms are taught...
python: How do I know what type of exception occurred?
I have a function called by the main program:
15 Answers
15
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How do you append to a file in Python?
...n C++. If you forget close(), it might take a while before the file is actually closed. It is easier that you might think to forget it when the code has multiple exit points, exceptions and so on.
– Petter
Jun 13 '13 at 17:37
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How can I search Git branches for a file or directory?
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git log + git branch will find it for you:
% git log --all -- somefile
commit 55d2069a092e07c56a6b4d321509ba7620664c63
Author: Dustin Sallings <dustin@spy.net>
Date: Tue Dec 16 14:16:22 2008 -0800
added somefile
% git branch -a --contains 55d2069
otherbranch
S...
Using wget to recursively fetch a directory with arbitrary files in it
... --cut-dirs=X (cuts out X directories). it's a bit annoying to have to manually count directories for X..
– lkraav
Nov 8 '10 at 21:49
3
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