I needed to write a weighted version of random.choice (each element in the list has a different probability for being selected). This is what I came up with: This function seems overly complex to me, and ugly. I’m hoping everyone here can offer some suggestions on improving it or alternate ways of doing this. Efficiency isn’t as important to me
Tag: optimization
Fastest way to list all primes below N
This is the best algorithm I could come up. Can it be made even faster? This code has a flaw: Since numbers is an unordered set, there is no guarantee that numbers.pop() will remove the lowest number from the set. Nevertheless, it works (at least for me) for some input numbers: Answer Warning: timeit results may vary due to differences
The Assignment Problem, a NumPy function?
Since an assignment problem can be posed in the form of a single matrix, I am wondering if NumPy has a function to solve such a matrix. So far I have found none. Maybe one of you guys know if NumPy/SciPy has an assignment-problem-solve function? Edit: In the meanwhile I have found a Python (not NumPy/SciPy) implementation at http://software.clapper.org/munkres/. Still
How to iterate over a list in chunks
I have a Python script which takes as input a list of integers, which I need to work with four integers at a time. Unfortunately, I don’t have control of the input, or I’d have it passed in as a list of four-element tuples. Currently, I’m iterating over it this way: It looks a lot like “C-think”, though, which makes
When is not a good time to use python generators?
This is rather the inverse of What can you use Python generator functions for?: python generators, generator expressions, and the itertools module are some of my favorite features of python these days. They’re especially useful when setting up chains of operations to perform on a big pile of data–I often use them when processing DSV files. So when is it