带有字符串的Python Itertools排列 [英] Python Itertools permutations with strings

问题描述

我想对字符串使用itertools排列，而不仅仅是字母.

i want to use itertools permutations for strings instead of just letters.

import itertools
lst = list(permutations(("red","blue"),3))
#This returns []

我知道我可以做类似的事情:

I know i can do something like:

a = list(permutations(range(3),3))
for i in range(len(a)):
a[i] = list(map(lambda x: 'red' if x==0 else 'blue' if x==1 else 'green',a[i]))

我想输入它作为输入，并得到它作为输出

I want to key in this as my input, and get this as my output

input: ("red","red","blue")

output:
[(’red’, ’red’, ’red’), (’red’, ’red’, ’blue’),\
(’red’, ’blue’, ’red’), (’red’, ’blue’, ’blue’), (’blue’, ’red’, ’red’), \
(’blue’, ’red’, ’blue’), (’blue’, ’blue’, ’red’), (’blue’, ’blue’, ’blue’)]

推荐答案

您可以像这样尝试itertools.product:

import itertools
lst = list(set(itertools.product(("red","red","blue"),repeat=3))) # use set to drop duplicates
lst

lst将是:

[('red', 'blue', 'red'),
 ('blue', 'red', 'red'),
 ('blue', 'blue', 'red'),
 ('blue', 'blue', 'blue'),
 ('blue', 'red', 'blue'),
 ('red', 'blue', 'blue'),
 ('red', 'red', 'blue'),
 ('red', 'red', 'red')]

更新:

import itertools
lst = list(itertools.product(("red","blue"),repeat=3))
lst

输出:

[('red', 'red', 'red'),
 ('red', 'red', 'blue'),
 ('red', 'blue', 'red'),
 ('red', 'blue', 'blue'),
 ('blue', 'red', 'red'),
 ('blue', 'red', 'blue'),
 ('blue', 'blue', 'red'),
 ('blue', 'blue', 'blue')]

这篇关于带有字符串的Python Itertools排列的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！