Puzzle 14 A Tale of One City
Pandas Brain Teasers — by Miki Tebeka (22 / 34)
Published in
3 min readMar 23, 2022
👈 A 10% Discount | TOC | Free-Range 👉
import pandas as pd
cities = pd.DataFrame([
('Vienna', 'Austria', 1_899_055),
('Sofia', 'Bulgaria', 1_238_438),
('Tekirdağ', 'Turkey', 1_055_412),
], columns=['City', 'Country', 'Population'])
def population_of(city):
return cities[cities['City'] == city]['Population']
city = 'Tekirdağ'
print(population_of(city))Guess the Output
IMPORTANT
Try to guess what the output is before moving to the next page.
This code will print: Series([], Name: Population, dtype: int64)
The output means we can’t find Tekirdağ in the cities DataFrame. But … it’s right there!
Let’s investigate:
In [1]: city
Out[1]: 'Tekirdağ'
In [2]: city2 = cities.loc[2]['City']
In [3]: city2
Out[3]: 'Tekirdağ'
In [4]: city2 == city
Out[4]: False
