Python Sets vs Lists

python list performance data-structures set
Mantas Vidutis picture Mantas Vidutis · May 14, 2010 · Viewed 156.6k times · Source

In Python, which data structure is more efficient/speedy? Assuming that order is not important to me and I would be checking for duplicates anyway, is a Python set slower than a Python list?

Answer

Michael Aaron Safyan picture Michael Aaron Safyan · May 14, 2010

It depends on what you are intending to do with it.

Sets are significantly faster when it comes to determining if an object is present in the set (as in x in s), but are slower than lists when it comes to iterating over their contents.

You can use the timeit module to see which is faster for your situation.

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