[Python] Pandas 'rename'-function not working within jupyter notebook?

I have a pandas dataframe ('df3') which columns I would like to rename.It is a subset of another dataframe, and I'm working in a jupyter notebook.

Getting all infos from the dataframe structure:

df3.info()

<class 'pandas.core.frame.DataFrame'>
RangeIndex: 29 entries, 104 to 132
Data columns (total 15 columns):
# Column Non-Null Count Dtype
--- ------ -------------- -----
0 Zählung in 28 non-null object
1 Unnamed: 17 29 non-null object
2 Unnamed: 18 29 non-null object
3 Unnamed: 19 29 non-null object
4 Unnamed: 20 29 non-null object
5 Unnamed: 21 29 non-null object
6 Unnamed: 40 29 non-null object
7 Unnamed: 41 29 non-null object
8 Unnamed: 42 29 non-null object
9 Unnamed: 43 28 non-null object
10 Unnamed: 44 28 non-null object
11 Unnamed: 63 29 non-null object
12 Unnamed: 64 29 non-null object
13 Unnamed: 65 29 non-null object
14 Unnamed: 66 28 non-null object
dtypes: object(15)
memory usage: 3.5+ KB



The columns need to be renamed by their index, so I create a dict with the index as keys and the new names as values:

col_names= {0:'Zeit',
1:'ZU_PKW',
2: 'ZU_LKW1',
3: 'ZU_LKW2',
4: 'ZU_SV',
5: 'ZU_SV%',
6:'AB_PKW',
7: 'AB_LKW1',
8: 'AB_LKW2',
9: 'AB_SV',
10: 'AB_SV%',
11:'ALL_PKW',
12: 'ALL_LKW1',
13: 'ALL_LKW2',
14: 'ALL_SV'
}



I tried to rename the columns with all options using the 'rename'-function:

1. Create a new dataframe with renamed columns without using inplace=True


df4 = df3.rename(index=col_names)


Result: no error, but the columns are not renamed

2. Create a new dataframe with renamed columns by using inplace=True


df4 = df3.rename(index={col_names, inplace = True)


Result: Error: A value is trying to be set on a copy of a slice from a DataFrame And the resulting df is None.

3. Change the dataframe directly by using inplace=True


df3.rename(index={col_names, inplace = True)


Result: `Error: A value is trying to be set on a copy of a slice from a DataFrame and the df3 stays unchanged.

4. Specifying also axis=1


df3.rename(index={col_names, inplace = True)


Returns TypeError: Cannot specify both 'axis' and any of 'index' or 'columns'

I feel I'm running out of options. What am I doing wrong? Could it have something to do with working in the jupyter notebook environment?

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