How to iterate over rows in a DataFrame in Pandas

1 min

Pandas gives you the ability to loop over columns and rows.

Here are the different ways to loop over columns or rows using the Pandas Library.

We define our DataFrame first

We define an example DataFrame.

import pandas as pd
df = pd.DataFrame({"firstname":["Caroline", "Sebastian", "Bob", "John"],
                   "lastname":["Jones", "Smith", "Di Caprio", "Lennon"],
                   "gpa":[4.1233, 2.242, 4.152,  5.923]})
We first define our DataFrame

Loop over a specific column using a for loop

for firstname in df["firstname"]:
	print(firstname)
We loop over a column and print the values

Loop over rows using apply

We usually use apply when we want to create another column with the current Data frame data.

df["fullname"] = df.apply(lambda row: f'{row["firstname"]} {row["lastname"]}', axis=1)
We loop over the rows using apply and axis=1

Loop over rows using iterrows()

for idx, row in df.iterrows():
    print(f"{row['student']} : {row['gpa']}")