Python lambda example | Code

As you know lambda expression is used to create a function without any name. We will see different Python lambda example program codes in this tutorial.

Syntax

lambda argument(s): expression

Python lambda examples

Simple example code.

Single argument adding example

Execute a lambda function on a single value.

res = lambda a: a + 10

print(res(10))

Output: 20

Multiple arguments Multipicaiton example

res = lambda a, b: a * b

print(res(10, 5))

Output: 50

Return Lambda Functions example

Double the given number.

def my_func(n):
    return lambda a: a * n


double_it = my_func(2)

print(double_it(5))

Output: 10

Example filter List using Lambda Functions

Using the filter() method to get the even from the given list.

list_1 = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

res = filter(lambda x: x % 2 == 0, list_1)

print(list(res))

Output:

Using map() function: Get cubes for every number in the list.

list_1 = [1, 2, 3, 4, 5]


cubed = map(lambda x: pow(x, 3), list_1)


print(list(cubed))

Output: [1, 8, 27, 64, 125]

Python Lambda example with apply() function by Pandas

Get the current age of each member.

import pandas as pd

df = pd.DataFrame({
    'Name': ['Annie', 'John', 'Tim', 'Mike'],
    'Status': ['Father', 'Mother', 'Son', 'Daughter'],
    'Birthyear': [1972, 1964, 2001, 2006],
})

df['age'] = df['Birthyear'].apply(lambda x: 2021 - x)

print(df)

Output:

Python Lambda Function with if-else

Lambda function to check if a given value is from 10 to 20

test = lambda x: True if (x > 10 and x < 20) else False

print((test(10)))

Output: False

Using lambda() Function with reduce()

from functools import reduce

li = [100, 200, 300]
sum = reduce((lambda x, y: x + y), li)

print(sum)

Output: 600

Do comment if you have any doubts or suggestions on this Python example code.

Note: IDE: PyCharm 2021.3.3 (Community Edition)

Windows 10

Python 3.10.1

All Python Examples are in Python 3, so Maybe its different from python 2 or upgraded versions.