Chapter 6.5 lambda.md

Chapter 6.5: Lambda Expressions

Table of Contents:

• Chapter 6.5: Lambda Expressions
  • Introduction
  • Lambda function with Zero arguments
  • Ternary operators on lambda functions

Introduction

In python Lambda functions or lambda expressions are single line expressions with no name that can have any number of arguments. Lambda functions are also called as anonymous functions or one-liner functions. Lambdas are useful when we have to do small repetitive tasks.

Basic Syntax:

value = lambda arg_1, arg_2, ..., arg_n : return_expression

here, everything separated with comma before : are arguments and the expression after : is used as the return value or expression. Lambda expression do not expect return keyword however whatever expression is written after the colon :, will be treated as return statement.

Example 1: A lambda to add 2 values

add_num = lambda a,b: a+b

print(add_num(5, 6))  # 11

Lambda function with Zero arguments

We can also create a lambda expression with zero arguments. To create a lambda with zero arguments, we just use lambda keyword before a colon :.

Example 2: Lambda to print Hello World

hello_world = lambda: "Hello World"

print(hello_world())    # Hello World

Ternary operators on lambda functions

odd_even = lambda num: 'Even' if num % 2 == 0 else 'Odd

print(odd_even(14))     # Even