Add data from multiple dataframe by its index using pandas

Question

So i got my dataframe (df1):

Number    Name       Gender  Hobby
122       John       Male      -
123       Patrick    Male      -
124       Rudy       Male      -

I want to add data to hobby based on number column. Assuming i've got my list of hobby based on its number on different dataframe. Like Example (df2):

Number    Hobby
124       Soccer
...         ...
...         ...

and df3 :

Number    Hobby
122       Basketball
...         ...
...         ...

How can i achieve this dataframe:

Number    Name       Gender  Hobby
122       John       Male    Basketball
123       Patrick    Male      -
124       Rudy       Male    Soccer

So far i've already tried this following solutions :

Select rows from a DataFrame based on values in a column in pandas

but its only selecting some data. How can i update the 'Hobby' column ? Thanks in advance.

im facing 2 dataframe here. each dataframe has different rows. i cant use that assignment. — Fregy, Jan 02 '18 at 05:23
how do you know which item belongs to which Number. Build a dictionary, list is of no use here then. — Bharath M Shetty, Jan 02 '18 at 05:26

score 0 · Answer 1 · answered Jan 02 '18 at 05:30

0

You can use map, merge and join will also achieve it

df['Hobby']=df.Number.map(df1.set_index('Number').Hobby)
df
Out[155]: 
   Number     Name Gender   Hobby
0     122     John   Male     NaN
1     123  Patrick   Male     NaN
2     124     Rudy   Male  Soccer

answered Jan 02 '18 at 05:30

BENY

317,841
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thank you. what if i've got another df and i want map it into multiple dataframe. in this case just df1, can i add with df1 and df2 as well? – Fregy Jan 02 '18 at 06:53
@Fregy yes you can repeat above – BENY Jan 02 '18 at 14:56

Add data from multiple dataframe by its index using pandas

1 Answers1