Filtering DataFrame Index through Array

Question

I have a sample dataframe df and an arraynas shown below. I want to filter based on the array values which are in index. The output dataframe is shown below as well. I have tried Out = df[df.index == n] and Out = df.loc[df.index == n ] which is not working giving an error Lengths must match to compare. Can anyone help me in solving this.

df = Date Open High Low Close Adj Close Volume 0 2007-06-18 0.33979 0.33979 0.33979 0.33979 0.33979 1591888 1 2007-06-29 0.33074 0.33074 0.33074 0.33074 0.33074 88440 2 2007-06-20 0.33526 0.33526 0.33526 0.33526 0.33526 3538 3 2007-06-21 0.32113 0.32113 0.32113 0.32113 0.32113 3550 4 2007-06-22 0.34713 0.34713 0.34713 0.34713 0.34713 670 6 2007-06-18 0.33979 0.33979 0.33979 0.33979 0.33979 1591888 7 2007-06-29 0.33074 0.33074 0.33074 0.33074 0.33074 88440 8 2007-06-20 0.33526 0.33526 0.33526 0.33526 0.33526 3538 9 2007-06-21 0.32113 0.32113 0.32113 0.32113 0.32113 3550 10 2007-06-22 0.34713 0.34713 0.34713 0.34713 0.34713 670

array([ 0, 1, 2, 3])

Out = Date Open High Low Close Adj Close Volume 0 2007-06-18 0.33979 0.33979 0.33979 0.33979 0.33979 1591888 1 2007-06-29 0.33074 0.33074 0.33074 0.33074 0.33074 88440 2 2007-06-20 0.33526 0.33526 0.33526 0.33526 0.33526 3538 3 2007-06-21 0.32113 0.32113 0.32113 0.32113 0.32113 3550

Answer 1

You should be able to do

out = df[df.index.isin(n)]

Answer 2

Your solutions do not work because you are trying to compare the equality value of your short array n and df.index. You can use pandas fancy-indexing to get your solution. The following will work fine if n is a np.array.

df.loc[n]