Pandas - Filter data frame with another data frame

Question

I have two data frames that have same length like this

df1: 
   density
1  1,45
2  3,87
3  4,35
4  2,87
5  0.74
6  9.34
7  3.087
8  0.28
9  6,47
10 5,59

The second data frame looks like this

I want an output that looks like this which means filter df1 in order to keep only values where df2 is equal to 1 :

output: 
   density
1  1,45
2  3,87
3  4,35
4  2,87
5  0.74
6  9.34

How can I do that? Can you help me please.

rafaelc · Accepted Answer · 2018-04-12 19:52:38Z

5

Let's use boolean index:

df1[df2.eq(1).values]

Output:

rafaelc

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answered Apr 12, 2018 at 19:47

Scott Boston

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1 Comment

@piRSquared Still confused which is my answer and which is Scott's

Scott Boston · Accepted Answer · 2018-04-12 19:53:35Z

5

This should work

df1[df2.State.astype(bool)]

Scott Boston

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answered Apr 12, 2018 at 19:46

rafaelc

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