Pandas .loc without KeyError

Question

>>> pd.DataFrame([1], index=[\'1\']).loc[\'2\']  # KeyError
>>> pd.DataFrame([1], index=[\'1\']).loc[[\'2\']]  # KeyError
>>> pd.DataFrame         


        

Answer 1

It seems to work fine for me. I'm running Python 3.5 with pandas version 0.20.3.

import numpy as np
import pandas as pd

# Create dataframe
data = {'distance': [0, 300, 600, 1000],
        'population': [4.8, 0.7, 6.4, 2.9]}
df = pd.DataFrame(data, index=['Alabama','Alaska','Arizona','Arkansas'])

keys = ['Alabama', 'Alaska', 'Arizona', 'Virginia']

# Create a subset of the dataframe.
df.loc[keys]
          distance  population
Alabama        0.0         4.8
Alaska       300.0         0.7
Arizona      600.0         6.4
Virginia       NaN         NaN

Or if you want to exclude the NaN row:

df.loc[keys].dropna()
          distance  population
Alabama        0.0         4.8
Alaska       300.0         0.7
Arizona      600.0         6.4