Lambda Functions Part 2

Part of the Logic & Flow section of Coddy's Python journey — lesson 58 of 78.

Lambda functions can also include conditional logic using the if-else expression syntax.

Create a basic lambda function with an if-else condition:

# Format: lambda parameters: value_if_true if condition else value_if_false
is_adult = lambda age: "Adult" if age >= 18 else "Minor"

Test the lambda function with different values:

print(is_adult(20))  # Output: "Adult"
print(is_adult(15))  # Output: "Minor"

You can use more complex conditions as well:

grade_status = lambda score: "Amazing!" if score == 100 else "Pass" if score >= 60 else "Fail"
print(grade_status(75))  # Output: "Pass"

Challenge

Easy

Create a lambda function named categorize_number that takes a number as an argument and returns:

"Positive" if the number is greater than 0
"Zero" if the number is equal to 0
"Negative" if the number is less than 0

Then use this lambda function to categorize a number received from input.

Cheat sheet

Lambda functions can include conditional logic using the if-else expression syntax:

# Basic if-else in lambda
is_adult = lambda age: "Adult" if age >= 18 else "Minor"

You can chain multiple conditions:

# Multiple conditions
grade_status = lambda score: "Amazing!" if score == 100 else "Pass" if score >= 60 else "Fail"

The format is: lambda parameters: value_if_true if condition else value_if_false

Try it yourself

# Read a number from input
number = int(input())

# Define your lambda function here
categorize_number = 

# Call your lambda function with the input number and print the result
print(categorize_number(number))

Test yourself

This lesson includes a short quiz. Start the lesson to answer it and track your progress.

All lessons in Logic & Flow

1Variables Exploration

Constants Multiple Variable Assignments Swapping Variables Placeholder Variables Round Numbers List Casting

4Contact Book Application

Display Menu Add Contact

7Sets Part 2

Mathematical Operations Part 1 Mathematical Operations Part 2 Recap - Treasure Hunt Subsets and Supersets Iterating Over Sets Recap - Tournament Tracker

10Basic List Comprehensions

The Syntax Creating Simple Lists Adding Conditions Using Data Aggregation Recap - House Of Lists Recap - Elements Of Freedom

13Inventory Management System

Project Overview Add Item

Update Stock

Check Availability

Generate Report

2Dictionaries Part 1

What is a Dictionary?Creating a Dictionary Accessing Values Modifying Dictionaries Recap - Recipe Manager

5Advanced Decision Making

Ternary Operator Membership Checks Identity Checks Indentation Errors Recap - Vacation Filter

8Student Records Manager

Project Overview Add Student

11Advanced Functions

Returning Multiple Values Lambda Functions Part 1Lambda Functions Part 2Recap Challenge - Lambda Sort Recursive Functions Part 1 Recursive Functions Part 2 Recap - Sum Nested List

14Higher-Order Functions

The Map Function The Filter Function Recap - Email Validator Recap - Number Processor

3Dictionaries Part 2

Dictionary Methods Nested Dictionaries Checking for Keys Looping Through Dictionaries Recap - Frequency Counter

6Sets Part 1

What is a Set?Basic Operations Set Methods Recap - Remove Duplicates

9Advanced Data Aggregation

Using Sum Finding Minimum and Maximum Sorting Data Efficiently Recap - Dictionary Sorter

12Basic Error Handling

What is Error Handling?The Try and Except Block Handling Multiple Exceptions Recap - Shopping Cart Errors

15Final Challenges

Smart Contact Manager Word Analytics Data Transformer