Python：当我使用findall（）提取一个数字时，输出是；[&"x27；39772&"x27；]；我该如何摆脱“我该怎么做？”；[&"x27；&"x27；]；所以我可以转换成浮动？

我使用re.findall（）从文件中的行中提取一个数字&我可以很好地得到这个数字，但是该函数添加了引号、双引号和方括号，因此我无法将字符串转换为浮点。如何从数字中去掉“[”]”字符以便转换它

这是我的密码：

import re
count = 0
total = list()
hand = open('mbox-short.txt')
for line in hand:
    line = line.rstrip()
    x = re.findall('New Revision: ([0-9.]+)', line)
    if len(x) > 0:
        count += 1
        a = str(x)
        total.append(a)
    
print(total)     # test print

total1 = list(map(float, total))          # line 24 -- where I get the ValueError

print(sum(total1)/count)

---

输出：

["['39772']", "['39771']", "['39770']", "['39769']", "['39766']", "['39765']", "['39764']", " 
['39763']", "['39762']", "['39761']", "['39760']", "['39759']", "['39758']", "['39757']", " 
['39756']", "['39755']", "['39754']", "['39753']", "['39752']", "['39751']", "['39750']", " 
['39749']", "['39746']", "['39745']", "['39744']", "['39743']", "['39742']"]
Traceback (most recent call last):
  File "revisions.py", line 27, in <module>
    total1 = list(map(float, total))
ValueError: could not convert string to float: ['39772']

[“['39772']”、“['39771']”、“['39770']”、“['39769']”、“['39766']”、“['39765']”、“['39764']”、”
['39763']", "['39762']", "['39761']", "['39760']", "['39759']", "['39758']", "['39757']", " 
['39756']", "['39755']", "['39754']", "['39753']", "['39752']", "['39751']", "['39750']", " 
['39749']", "['39746']", "['39745']", "['39744']", "['39743']", "['39742']"]
回溯（最近一次呼叫最后一次）：
文件“revisions.py”，第27行，在
total1=列表（映射（浮动，总计））
ValueError:无法将字符串转换为浮点：['39772']

---

我试着把数字转换成浮点数，这样我就能计算出平均数。 我错过了什么？在哪里可以找到有关操作输出格式的信息，以便使用它

谢谢大家!

s = "['123']"

s = s[2:-2] # remove first 2 and last 2 characters

print(float(s))
# 123.0

---

只需从字符串中去掉前两个和后两个字符。

使用列表理解将

total

中的所有值转换为float

total=[float（i.split（“”）[1]）表示i总计]

不要做

a=str（x）

直接追加

x

它不会让我；我有一个关于元组的错误。