Pass the name of the dataframe into each for row for a new column in a list of dataframes Python

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I have a list of dataframes, I want to add a new column to each dataframe that is the name of the dataframe.

df_all = [df1,df2,df3]

for df in df_all:
    df["Loc"] = df[df].astype.(str)

Boolean array expected for the condition, not object

is this possible to achieve?

list dataframe pandas python
2 Answers

You can't do this, python objects have no possibility to know their name(s).

You could emulate it with:

df_all = [df1, df2, df3]

for i, df in enumerate(df_all, start=1):
    df['Loc'] = f'df{i}'

Alternatively, use a dictionary:

df_all = {'df1': df1, 'df2': df2, 'df3': df3}

for k, df in df_all.items():
    df['Loc'] = k
mozway0

It can be done with using the system's locals() dictionary, which contains variable names and references, and the is operator to match.

df1, df2, df3 = pd.DataFrame([1, 1, 1]), pd.DataFrame([2, 2, 2]), pd.DataFrame([3, 3, 3])

df_all = [df1, df2, df3]

_df = k = v = None
for _df in df_all:
    for k, v in locals().items():
        if v is _df and k != '_df':
            _df["Loc"] = k

print(*df_all, sep='\n\n')

   0  Loc
0  1  df1
1  1  df1
2  1  df1

   0  Loc
0  2  df2
1  2  df2
2  2  df2

   0  Loc
0  3  df3
1  3  df3
2  3  df3
Алексей Р0
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