Pandas index isin method

Question

I'm having throuble working with the isin method when working with pandas indexes, it always returns False.

from pandas import DataFrame
df = DataFrame(data=[['a', 1], ['b', 2], ['c', 3]], index=['N01', 'N02', 'N03'])
df.index.isin(['01', '02'])

returns

array([False, False, False], dtype=bool)

Answer 1

Use str.contains and pass a regex pattern:

In[5]: df.index.str.contains('01|02')

Out[5]: array([ True,  True, False], dtype=bool)

isin looks for exact matches which is why you get all False array returned