如何在数据帧的每一行中添加元素？

Question

I have three types of columns in my dataframe: numeric, string and datetime.

I need to add the element | to the end of every value as a separator

I have tried:

df['column'] = (df['column']+ '|')

but it does not work for the datetime columns and I have to add .astype(str) to the numeric columns which may result in formatting issues later.

Any other suggestions?

Answer 1

you can use DataFrame.to_csv() with sep="|", if you want to create a csv.

further documentation : https://pandas.pydata.org/pandas-docs/stable/reference/api/pandas.DataFrame.to_csv.html

Answer 2

Not too sure why you would want to do this but if you want to make a CSV file with | as the delimiter, you can set that in the df.to_csv('out.csv', sep='|') method. I think a cleaner way of doing this would be to use a lambda function:

df['column'] = df['column'].apply(lambda x: f"{x}|")

You will always have to add .astype(str) though...

Answer 3

在这种情况下，这可能对您有帮助：

df['column'] = df['column'].astype(str) + "|"