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pythongeneratorstd

Python generator that groups another iterable into groups of N

I'm looking for a function that takes an iterable i and a size n and yields tuples of length n that are sequential values from i:

x = [1,2,3,4,5,6,7,8,9,0]
[z for z in TheFunc(x,3)]

gives

[(1,2,3),(4,5,6),(7,8,9),(0)]

Does such a function exist in the standard library?

If it exists as part of the standard library, I can't seem to find it and I've run out of terms to search for. I could write my own, but I'd rather not.

Solution

  • See the grouper recipe in the docs for the itertools package 

    def grouper(n, iterable, fillvalue=None):
  "grouper(3, 'ABCDEFG', 'x') --> ABC DEF Gxx"
  args = [iter(iterable)] * n
  return izip_longest(fillvalue=fillvalue, *args)

    (However, this is a duplicate of quite a few questions.)