How should I filter one dataframe by entries from another one in pandas with isin?

Question

I have two dataframes (df1, df2). The columns names and indices are the same (the difference in columns entries). Also, df2 has only 20 entries (which also existed in df1 as i said). I want to filter df1 by df2 entries, but when i try to do it with isin but nothing happens.

df1.isin(df2) or df1.index.isin(df2.index)

Tell me please what I'm doing wrong and how should I do it..

I am sure you can find your answer by searching for this. How about ```df1.loc[df2.index]``` ? — sophocles, Jan 03 '22 at 11:22

score 1 · Answer 1 · answered Jan 03 '22 at 11:27

First of all the isin function in pandas returns a Dataframe of booleans and not the result you want. So it makes sense that the cmds you used did not work.

I am possitive that hte following psot will help

pandas - filter dataframe by another dataframe by row elements

Thrasy · Accepted Answer · 2022-01-03T12:44:55.770

0

If you want to select the entries in df1 with an index that is also present in df2, you should be able to do it with:

df1.loc[df2.index]

or if you really want to use isin:

df1[df1.index.isin(df2.index)]

edited Jan 03 '22 at 12:44

answered Jan 03 '22 at 11:25

Thrasy

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Such a easy way, and i even didn't try to do that.. Thank you kindly.. – Yonko Jan 03 '22 at 12:06

How should I filter one dataframe by entries from another one in pandas with isin?

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