X-Git-Url: https://wannabe.guru.org/gitweb/?a=blobdiff_plain;f=list_utils.py;h=7f28ade922a4b733ee29ea0c68bc957ff587c51b;hb=c6fca944b41f292b66efaba27ebf3fd0a37956b8;hp=d70159a1b2dadb61640eae20f029608cabd2f46e;hpb=5317c50ce7a96a37acfab3800c0935580766dbbf;p=python_utils.git diff --git a/list_utils.py b/list_utils.py index d70159a..7f28ade 100644 --- a/list_utils.py +++ b/list_utils.py @@ -1,8 +1,11 @@ #!/usr/bin/env python3 +"""Some useful(?) utilities for dealing with Lists.""" + +import random from collections import Counter from itertools import islice -from typing import Any, Iterator, List, Mapping, Sequence, Tuple +from typing import Any, Iterator, List, MutableSequence, Sequence, Tuple def shard(lst: List[Any], size: int) -> Iterator[Any]: @@ -230,9 +233,31 @@ def _permute(seq: str, path: str): yield from _permute(cdr, path + car) -def binary_search( - lst: Sequence[Any], target: Any, *, sanity_check=False -) -> Tuple[bool, int]: +def shuffle(seq: MutableSequence[Any]) -> MutableSequence[Any]: + """Shuffles a sequence into a random order. + + >>> random.seed(22) + >>> shuffle([1, 2, 3, 4, 5]) + [3, 4, 1, 5, 2] + + >>> shuffle('example') + 'empaelx' + + """ + if isinstance(seq, str): + import string_utils + + return string_utils.shuffle(seq) + else: + random.shuffle(seq) + return seq + + +def scramble(seq: MutableSequence[Any]) -> MutableSequence[Any]: + return shuffle(seq) + + +def binary_search(lst: Sequence[Any], target: Any, *, sanity_check=False) -> Tuple[bool, int]: """Performs a binary search on lst (which must already be sorted). Returns a Tuple composed of a bool which indicates whether the target was found and an int which indicates the index closest to @@ -267,9 +292,7 @@ def binary_search( return _binary_search(lst, target, 0, len(lst) - 1) -def _binary_search( - lst: Sequence[Any], target: Any, low: int, high: int -) -> Tuple[bool, int]: +def _binary_search(lst: Sequence[Any], target: Any, low: int, high: int) -> Tuple[bool, int]: if high >= low: mid = (high + low) // 2 if lst[mid] == target: