python 小知識點 多字串替換

乙個長字串或者乙個文字檔案做資料分析的時候經常遇到需要排除干擾項的需求，這時候就需要多字串替換的功能

使用str的 replace函式

字串常用的替換函式

比如說將標點替換成空，使用replace連續替換多次即可

s = '''

there was a card party at the rooms of naroumoff, of the horse guards. 
the long winter night passed away imperceptibly, and it was five o'clock in the morning before the company sat down
'''b = s.replace(",", "").replace(".", "").replace(";", "")
print(b)

import re

s = '''
there was a card party at the rooms of naroumoff, of the horse guards. 
the long winter night passed away imperceptibly, and it was five o'clock in the morning before the company sat down
'''words = ["when", "there", "those", "the"]
def replace_re():
pattern = re.compile("|".join(words))
print(pattern)
r = re.sub(pattern, "", s)	# 全部替換成空
print(r)

import re

s = '''
there was a card party at the rooms of naroumoff, of the horse guards. 
the long winter night passed away imperceptibly, and it was five o'clock in the morning before the company sat down
'''words = 
def replace_re():
rep = dict((re.escape(k), v) for k, v in words.items())
pattern = re.compile("|".join(rep.keys()))
r = pattern.sub(lambda m: rep[re.escape(m.group(0))], s)
print(r)

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