Some years ago I did some of these problems in Haskell in order to learn the language a bit.

Now I'm doing some in Python 3. I already know Python, but I rarely do mathematical stuff, or have to think about efficiency.

The solution to problem 3 is the function named f in the module pe003.py. Usually. Sometimes you will find two functions, f0 and f1. In this case, f0 is the easy-to-read function I would normally write, and f1 is the one that performs well.

You will also find test_f functions in each module, these are for running with py.test. Unfortunately, these will give away the solution, but I'm sure others on the Internet have done that already.

The one-minute rule that Project-Euler mentions is surely a bit outdated. I'm including my timeit results in the docstring of each function, and I try to keep individual problems under one second.

I'll try to keep the cumulative computation time under 1 minute. Currently all tests can be run in under twenty seconds on my machine.

On my machine, I run tests with:

$ python3 -m pytest

Since $ py.test alone uses python 2.