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Python extending with - using super() Python 3 vs Python 2
Originally I wanted to ask this question , but then I found it was already thought of before...
5 Answers
...
What are metaclasses in Python?
...ass is an instance of a metaclass.
While in Python you can use arbitrary callables for metaclasses (like Jerub shows), the better approach is to make it an actual class itself. type is the usual metaclass in Python. type is itself a class, and it is its own type. You won't be able to recreate somet...
How to obtain the number of CPUs/cores in Linux from the command line?
... Note that both of these will end up counting twice as many cores as actually exist if you're on a system with hyperthreading (e.g, P4, or Core i7).
– duskwuff -inactive-
Jun 26 '11 at 0:04
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Bidirectional 1 to 1 Dictionary in C#
...turn firstToSecond.Count; }
}
/// <summary>
/// Removes all items from the dictionary.
/// </summary>
public void Clear()
{
firstToSecond.Clear();
secondToFirst.Clear();
}
}
...
How do I uniquely identify computers visiting my web site?
..., fingerprints changed quite
rapidly, but even a simple heuristic was usually able to guess when a fingerprint was an “upgraded” version of a previously observed browser’s
fingerprint, with 99.1% of guesses correct and a false positive rate of only
0.86%.
We discuss what privacy thr...
Casting vs using the 'as' keyword in the CLR
...d within the if body.) That's slightly annoying in some cases, so if you really care about introducing the smallest number of variables possible in every scope, you might still want to use is followed by a cast.
I don't think any of the answers so far (at the time of starting this answer!) have r...
How do I create an average from a Ruby array?
...void integer division or your results will be wrong. Also, this isn't generally applicable to every possible element type (obviously, an average only makes sense for things that can be averaged). But if you want to go that route, use this:
class Array
def sum
inject(0.0) { |result, el| result...
capturing self strongly in this block is likely to lead to a retain cycle
...
Good answer, but I take small issue with you saying: “you can't refer to self or properties on self from within a block that will be strongly retained by self.” This is not strictly true. Please see my answer below. Better to say, “you must take...
What is the copy-and-swap idiom?
...s arguably the most nuanced and difficult. How should it be done? What pitfalls need to be avoided?
The copy-and-swap idiom is the solution, and elegantly assists the assignment operator in achieving two things: avoiding code duplication, and providing a strong exception guarantee.
How does it wor...
How to print a dictionary line by line in Python?
...
Hmm. I think my problem is even worse than that. Basically I've parsed out some data from an HTML table, and I happened to store it in a dictionary, and now I'm trying to take that dictionary data and put it into a DataFrame before I export it all to an Oracle table....it's pret...