Question

我需要一个包含与模式完全相同的单词的输出-仅在相同位置出现相同的字母（并且单词不应在其他位置显示）例如：

words = ['hatch','catch','match','chat','mates'] 
pattern = '_atc_

所需的输出：

['hatch','match']

我尝试使用嵌套的循环，但不适用于以'_'开头和结尾的模式

def filter_words_list(words, pattern):
relevant_words = []
for word in words:
    if len(word) == len(pattern):
        for i in range(len(word)):
            for j in range(len(pattern)):
                if word[i] != pattern[i]:
                    break
                if word[i] == pattern[i]:
                    relevant_words.append(word)

thx！

Answer 1

您可以使用regular expression：

import re

words = ['hatch','catch','match','chat','mates']
pattern = re.compile('[^atc]atc[^atc]')

result = list(filter(pattern.fullmatch, words))
print(result)

输出

['hatch', 'match']

模式'[^atc]atc[^atc]'匹配不等于a或t或c（[^atc]）的所有内容，后跟'atc'匹配不等于a或t或c的所有内容。

作为替代方案，您可以编写自己的匹配函数，该函数将与任何给定模式一起使用：

from collections import Counter


def full_match(word, pattern='_atc_'):
    if len(pattern) != len(word):
        return False

    pattern_letter_counts = Counter(e for e in pattern if e != '_')  # count characters that are not wild card
    word_letter_counts = Counter(word) # count letters

    if any(count != word_letter_counts.get(ch, 0) for ch, count in pattern_letter_counts.items()):
        return False

    return all(p == w for p, w in zip(pattern, word) if p != '_')  # the word must match in all characters that are not wild card


words = ['hatch', 'catch', 'match', 'chat', 'mates']


result = list(filter(full_match, words))
print(result)

输出

['hatch', 'match']

进一步

请参阅有关内置函数any和all的文档。
请参阅Counter上的文档。

Answer 2

因此，您应该使用正则表达式。并用“。”替换下划线。表示任何单个字符。因此输入如下：

words = ['hatch','catch','match','chat','mates'] 
pattern = '.atc.'

，代码为：

import re
def filter_words_list(words, pattern):
ret = []
for word in words:
    if(re.match(pattern,word)):ret.append(word)
return ret

希望得到帮助

检查模式是否在单词列表中

2 个答案: