itertools module - combinatoric iterators

By Martin McBride, 2022-08-18
Tags: product permutations combinations itertools python standard library
Categories: python standard library


The itertools module provides several combinatoric iterators. These functions take one or more input iterables and return an iterator that provides a specific set of combinations of the elements of those iterables.

The itertools functions in this section are:

  • Cartesian product - generates the cartesian product of two or more lists.
  • Permutations - generates all possible permutations of items from a list.
  • Combinations - generates all possible combinations of items from a list. When using the combinations, an item cannot be used more than once (that is sometimes called combinations without replacement). Alternatively, the combinations_with_replacement function generates all possible combinations of items from a list with, replacements. That means that an item from the list can be used more than once.

The functions can be applied to lists or more generally to any iterable data.

See also

If you found this article useful, you might be interested in the book NumPy Recipes or other books by the same author.

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