python-3.x - 使用 python 替换数据框中列的多个字符

Question

我试图同时用一个字符替换多个字符，但我做不到

df = pandas.DataFrame({"Col1":["A", "B", "ABC", "D", "AB"], "Col2":["H", "I", "J", "K", "L"]})

>>> df
       Col1       Col2
0         A          H
1         B          I
2       ABC          J
3         D          K
4        AB          L

替换数据框中某列的多个字符

df['Col1'] = df['Col1'].str.replace(['C','D'],'W')

>>>
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "C:\Users\Laura\AppData\Local\Programs\Python\Python37-32\lib\site-packages\pandas\core\strings.py", line 1954, in wrapper
    return func(self, *args, **kwargs)
  File "C:\Users\Laura\AppData\Local\Programs\Python\Python37-32\lib\site-packages\pandas\core\strings.py", line 2777, in replace
    self._parent, pat, repl, n=n, case=case, flags=flags, regex=regex
  File "C:\Users\Laura\AppData\Local\Programs\Python\Python37-32\lib\site-packages\pandas\core\strings.py", line 713, in str_replace
    compiled = re.compile(pat, flags=flags)
  File "C:\Users\Laura\AppData\Local\Programs\Python\Python37-32\lib\re.py", line 234, in compile
    return _compile(pattern, flags)
  File "C:\Users\Laura\AppData\Local\Programs\Python\Python37-32\lib\re.py", line 276, in _compile
    return _cache[type(pattern), pattern, flags]
TypeError: unhashable type: 'list'

如果有效的话可以单独使用，但我认为这不是最好的方法

df['Col1'] = df['Col1'].str.replace('C','W')
df['Col1'] = df['Col1'].str.replace('D','W')

>>> df
       Col1       Col2
0         A          H
1         B          I
2       ABW          J
3         W          K
4        AB          L

我怎样才能同时或更有效地做到这一点？

Answer 1

str.replace中的字符串是正则表达式模式，因此您可以利用它:

df['Col1'] = df['Col1'].str.replace(r'C|D','W')

print(df)

打印:

  Col1 Col2
0    A    H
1    B    I
2  ABW    J
3    W    K
4   AB    L