Python Dataframe rename column compared to value-CodePudding

With Pandas I'm trying to rename unnamed columns in dataframe with values on the first ligne of data.

My dataframe:

id    store   unnamed: 1 unnamed: 2 windows unnamed: 3 unnamed: 4
0       B1     B2          B3         B1     B2          B3         
1       2      c           12         15     15          14
2       4      d           35         14     14          87

My wanted result:

id    store_B1   store_B2  store_B3    windows_B1 windows_B2 windows_B3
0       B1          B2        B3           B1        B2          B3         
1       2           c         12           15        15          14
2       4           d         35           14        14          87

I don't know how I can match the column name with the value in my data. Thanks for your help. Regards

CodePudding user response：

You can use df.columns.where to make unnamed: columns NaN, then convert it to a Series and use ffill:

df.columns = pd.Series(df.columns.where(~df.columns.str.startswith('unnamed:'))).ffill()   np.where(~df.columns.isin(['id','col2']), ('_'   df.iloc[0].astype(str)).tolist(), '')

Output:

>>> df
   id store_B1 store_B2 store_B3 windows_B1 windows_B2 windows_B3
0   0       B1       B2       B3         B1         B2         B3
1   1        2        c       12         15         15         14
2   2        4        d       35         14         14         87