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Why does += behave unexpectedly on lists?
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The general answer is that += tries to call the __iadd__ special method, and if that isn't available it tries to use __add__ instead. So the issue is with the difference between these special methods.
The __iadd__ special method is for an in-place addition, that i...
How does python numpy.where() work?
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How do they achieve internally that you are able to pass something like x > 5 into a method?
The short answer is that they don't.
Any sort of logical operation on a numpy array returns a boolean array. (i.e. __gt__, __lt__, etc all return boolea...
What does the “yield” keyword do?
... list, you can read its items one by one. Reading its items one by one is called iteration:
>>> mylist = [1, 2, 3]
>>> for i in mylist:
... print(i)
1
2
3
mylist is an iterable. When you use a list comprehension, you create a list, and so an iterable:
>>> mylist = [...
Build an ASCII chart of the most commonly used words in a given text [closed]
... LabVIEW's very happy in its hardware control and measurement niche, but really pretty awful for string manipulation.
– Joe Z
Jul 4 '10 at 6:23
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How to suppress “unused parameter” warnings in C?
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I usually write a macro like this:
#define UNUSED(x) (void)(x)
You can use this macro for all your unused parameters. (Note that this works on any compiler.)
For example:
void f(int x) {
UNUSED(x);
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}
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difference between variables inside and outside of __init__()
Is there any difference at all between these classes besides the name?
10 Answers
10
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How to avoid having class data shared among instances?
...problem you face is that x.list and y.list are the same list, so when you call append on one, it affects the other.
– Matt Moriarity
Nov 5 '09 at 14:04
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Define a lambda expression that raises an Exception
...ur goal is to avoid a def, this obviously doesn't cut it. It does, however allow you to conditionally raise exceptions, e.g.:
y = lambda x: 2*x if x < 10 else raise_(Exception('foobar'))
Alternatively you can raise an exception without defining a named function. All you need is a strong stom...
Find which commit is currently checked out in Git
...detached at c1abcde <== RIGHT HERE
Option 5: git bisect visualize
Finally, while you're doing a git bisect, you can also simply use git bisect visualize or its built-in alias git bisect view to launch gitk, so that you can graphically view which commit you are on, as well as which commits you ...
Short description of the scoping rules?
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Actually, a concise rule for Python Scope resolution, from Learning Python, 3rd. Ed.. (These rules are specific to variable names, not attributes. If you reference it without a period, these rules apply.)
LEGB Rule
Local — N...