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

Using the sample dataframe from @binjip's answer:

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']

Get matching records from the dataframe. NB: The dataframe index must be unique for this to work!

df.reindex(keys)

          distance  population
Alabama        0.0         4.8
Alaska       300.0         0.7
Arizona      600.0         6.4
Virginia       NaN         NaN

If you want to omit missing keys:

df.reindex(df.index.intersection(keys))

         distance  population
Alabama         0         4.8
Alaska        300         0.7
Arizona       600         6.4