.isin() function is returning an empty set when filtering an object column in DataFrame-CodePudding

Reading and appending excel files to create DataFrame:

import pandas as pd
import os

folder = r'C:\mypathtodocuments'
files = os.listdir(folder)

df = pd.DataFrame()

for file in files:
    if file.endswith('.xlsx'):
        df = df.append(pd.read_excel(os.path.join(folder,file)))

#Drop extra columns from wrong data
df1 = df[['FIRST_NM', 'LAST_NM', 'CITY_AD']]

Preview of CITY_AD column:

>>> df1["CITY_AD"]

0      EL PASO
1      HOUSTON
2      HOUSTON
3      CONROE
4      MCKINNEY
5      MCKINNEY
6      KATY
7      TOMBALL
8      TOMBALL
9      SPRING
10     SPRING

Filter DataFrame with .isin() function to only include cities HOUSTON and CONROE:

df1[df1["CITY_AD"].isin(["HOUSTON","CONROE"])]

This returns an empty set... How can I get it to filter correctly?

CodePudding user response：

Try this:

df1["CITY_AD"] = df1["CITY_AD"].str.strip()
df1[df1["CITY_AD"].isin(["HOUSTON","CONROE"])]