8000 Misc cleanups and wording improvements for the itertools docs by rhettinger · Pull Request #119626 · python/cpython · GitHub
[go: up one dir, main page]
Skip to content

Misc cleanups and wording improvements for the itertools docs #119626

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 16 commits into from
May 27, 2024
Merged

Misc cleanups and wording improvements for the itertools docs #119626

Changes from 1 commit
Commits
Show all changes
16 commits
Select commit Hold shift + click to select a range
e42bf24
Tighten the wording for permutations(). Add links.
rhettinger May 25, 2024
2c2bb68
Tighten the wording for combinations(). Add links.
rhettinger May 25, 2024
269b506
Tighten the wording for combinations_with_replacement().
rhettinger May 25, 2024
642e89f
Tighen wording for islice()
rhettinger May 25, 2024
c581a38
Swap sentence order
rhettinger May 26, 2024
598c414
.
rhettinger May 26, 2024
a558705
Sync table examples with main docs
rhettinger May 27, 2024
2974acd
Improve readability of the amortization example
rhettinger May 27, 2024
295baa4
Improve accumulate() docs
rhettinger May 27, 2024
d3e6800
.
rhettinger May 27, 2024
1f52c89
Improve wording for compress()
rhettinger May 27, 2024
95f503b
Improve wording for count()
rhettinger May 27, 2024
61f629d
Tighter wording for cycle()
rhettinger May 27, 2024
95e82ed
Improve wording for dropwhile()
rhettinger May 27, 2024
6cfce87
Misc wording tweaks
rhettinger May 27, 2024
d60c375
Tweak starmap() wording
rhettinger May 27, 2024
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
Prev Previous commit
Next Next commit
Tighten the wording for combinations_with_replacement().
  • Loading branch information
@rhettinger
rhettinger committed May 25, 2024
commit 269b5062a20e68ace37ee7a86f9d23c9b1c5e8df
22 changes: 7 additions & 15 deletions Doc/library/itertools.rst
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -271,12 +271,17 @@ loops that truncate the stream.
Return *r* length subsequences of elements from the input *iterable*
allowing individual elements to be repeated more than once.

The output is a subsequence of :func:`product` that keeps only entries
that are subsequences (with possible repeated elements) of the
*iterable*. The number of subsequence returned is ``(n + r - 1)! / r! /
(n - 1)!`` when ``n > 0``.

The combination tuples are emitted in lexicographic order according to
the order of the input *iterable*. So, if the input *iterable* is sorted,
the order of the input *iterable*. if the input *iterable* is sorted,
the output tuples will be produced in sorted order.

Elements are treated as unique based on their position, not on their
value. So, if the input elements are unique, the generated combinations
value. If the input elements are unique, the generated combinations
will also be unique.

Roughly equivalent to::
Expand All @@ -298,19 +303,6 @@ loops that truncate the stream.
indices[i:] = [indices[i] + 1] * (r - i)
yield tuple(pool[i] for i in indices)

The code for :func:`combinations_with_replacement` can be also expressed as
a subsequence of :func:`product` after filtering entries where the elements
are not in sorted order (according to their position in the input pool)::

def combinations_with_replacement(iterable, r):
pool = tuple(iterable)
n = len(pool)
for indices in product(range(n), repeat=r):
if sorted(indices) == list(indices):
yield tuple(pool[i] for i in indices)

The number of items returned is ``(n+r-1)! / r! / (n-1)!`` when ``n > 0``.

.. versionadded:: 3.1


Expand Down
0