python - How to merge two DataFrames of unequal size based on row value -

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i have 2 pandas dataframes of type

dataframe 1  index   name    property1 property2 0     ("a","b")  1          2 1     ("c","d")  3          4 2     ("e","f")  5          6

and second 1 , has common values , not @ same index ( dont care about).

dataframe 2  index   name    property3 property4 0     ("g","h")  7          8 1     ("i","j")  9          10 2     ("k","l")  11         12 3     ("a","b")  13         14 4     ("c","d")  15         16 5     ("e","f")  17         18

is there way these combined such resultant dataframe common rows name shared between tables?

i.e result of pandas operation should be

result frame  index    name    property1 property2 property3 property4 0      ("a","b")  1         2           13       14    1      ("c","d")  3         4           15       16 2      ("e","f")  5         6           17       18

sorry not giving actual pandas code create dataframes above. want conceptually understand how join 2 unequal sized dataframes different "indexes" based on column name . tried merge , concat , join dont result want.

a default merge works fine here, assuming index index:

in [22]:  df1.merge(df2) out[22]:         name  property1  property2  property3  property4 0  ("a","b")          1          2         13         14 1  ("c","d")          3          4         15         16 2  ("e","f")          5          6         17         18

here merge looks common columns , performs inner merge on columns.

you can explicit , specify want merge on 'name' column:

df1.merge(df2, on='name')

but in case it's not necessary because common column 'name' anyway.


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