Control Flow in Python: if, else, and elif Statements

Introduction

Welcome back to our Python tutorial series on CipherTrick.com! In this tutorial, we’ll explore control flow in Python, particularly focusing on if, else, and elif statements. Control flow is the order in which the program’s code executes. The control flow of a Python program is regulated by conditional statements, loops, and function calls.

Part 1: The if Statement

The if statement is used in Python for decision-making operations. It contains a logical expression, and if this expression is True, Python executes the code block within the if statement.

num = 10

if num > 0:
    print("The number is positive.")

In the above code, Python will print “The number is positive.” because the condition num > 0 is True.

Part 2: The else Statement

The else statement complements the if statement. An else statement contains the block of code that executes if the if statement’s logical expression is False.

num = -1

if num > 0:
    print("The number is positive.")
else:
    print("The number is not positive.")

In the above code, Python will print “The number is not positive.” because the condition num > 0 is False.

Part 3: The elif Statement

The elif statement allows you to check multiple expressions for True and execute a block of code as soon as one of the conditions evaluates to True. It’s a way of saying “if the previous conditions were not true, then try this condition”.

num = 0

if num > 0:
    print("The number is positive.")
elif num == 0:
    print("Zero is neither positive nor negative.")
else:
    print("The number is negative.")

In the above code, Python will print “Zero is neither positive nor negative.” because the condition num == 0 is True.

Conclusion

Understanding control flow is a crucial aspect of Python programming. The if, else, and elif statements offer us robust tools to direct the flow of a program. They allow us to create more complex and intelligent programs that can make decisions and respond to different inputs or situations. Keep practicing these concepts to understand their implementation better. In our next tutorials, we’ll cover more control flow tools like loops and functions. Stay tuned and keep coding!