How to remove all special characters and letters from column in DataFrame in Python Pandas?

Question

I have DataFrame like below in Python Pandas ("col1" is data type string):

col1
-----
1234AABY332
857363opx00C*+
9994TyF@@@!
...

And I need to remove all special characters like: ["-", ",", ".", ":", "/", "@", "#", "&", "$", "%", "+", "*", "(", ")", "=", "!", " ", "~", "~ "] and letters (both large and small) like for example: A, a, b, c and so one...

so as a result I need DataFrame like below:

col1
-----
1234332
85736300
9994
...

How can I do that in Python Pandas ?

Answer 1

我可能会将您的要求表述为删除所有非数字字符：

df["col1"] = df["col1"].str.replace(r'\D+', '', regex=True)

Answer 2

You can also use findall to extract digit only:

df['col1'] = df['col1'].str.findall(r'(\d)').str.join('')
print(df)

# Output
       col1
0   1234332
1  85736300
2      9994

You can append .astype(int) to convert digits to a number: