On Sun, Sep 8, 2013 at 9:32 PM, Guido van Rossum <guido@python.org> wrote:

- Parallel arrays or arrays of tuples? I think the API should require
an array of tuples. It is trivial to zip up parallel arrays to the
required format, while if you have an array of tuples, extracting the
parallel arrays is slightly more cumbersome.

I agree with your conclusion but not with the rationale: converting between array of tuples and parallel arrays is trivial both ways:

>>> at = [(1,2,3), (4,5,6), (7,8,9), (10, 11, 12)]

>>> zip(*at)

[(1, 4, 7, 10), (2, 5, 8, 11), (3, 6, 9, 12)]

>>> zip(*_)

[(1, 2, 3), (4, 5, 6), (7, 8, 9), (10, 11, 12)]

(Note that zip(*x) is basically transpose(x).)