如何从字符串Python熊猫中提取数字和字符？

Question

我有一个混合数字和字符数据的数据集。我只想提取数字数据和字母"W“(我不需要'2×HDMI \2×USB‘.)。

例如在本例中(20W，30W等)。谢谢你的帮助

v=['2 x HDMI | 2 x USB', '20 W Speaker Output', '10 W Speaker Output',
       '20 W Speaker Output', '20 W Speaker Output',
       '20 W Speaker Output', '20 W Speaker Output', '20 Speaker Output',
       '20 W Speaker Output', '20 W Speaker Output',
       '30 W Speaker Output', '20 W Speaker Output',
       '20 W Speaker Output', '2 x HDMI | 2 x USB', '20 W Speaker Output',
       '20 Speaker Output', '24 W Speaker Output', '20 W Speaker Output']

df=pd.DataFrame({"col_1":v})

Answer 1

您可以使用正则表达式和一些列表理解技巧来获得您想要的：

import re
import pandas as pd

v=['2 x HDMI | 2 x USB', '20 W Speaker Output', '10 W Speaker Output',
       '20 W Speaker Output', '20 W Speaker Output',
       '20 W Speaker Output', '20 W Speaker Output', '20 Speaker Output',
       '20 W Speaker Output', '20 W Speaker Output',
       '30 W Speaker Output', '20 W Speaker Output',
       '20 W Speaker Output', '2 x HDMI | 2 x USB', '20 W Speaker Output',
       '20 Speaker Output', '24 W Speaker Output', '20 W Speaker Output']

df=pd.DataFrame({"col_1":[v.group(0) for v in [re.search('\d+\s?[Ww]', v) for v in v] if v]})

..。在以下方面的成果：

>>> df
   col_1
0   20 W
1   10 W
2   20 W
3   20 W
4   20 W
5   20 W
6   20 W
7   20 W
8   30 W
9   20 W
10  20 W
11  20 W
12  24 W
13  20 W

Answer 2

尝试：

import re
for x in v:
    ms = re.compile(r'\d+\s[wW]')
    m = re.search(ms, x)
    print(m.group())

Answer 3

print(df['col_1'].str.extract(r'(\d+ [W])*'))

这上面的提取方法用正则表达式，会像预期的那样进行过滤，然后清除Nan值。