If Else Statement In Python

Python If Else Statements: Conditional Statements

If-else statements or conditional statements are fundamental Python structures for making decisions based on a given condition. These statements are frequently used in organizations to develop sophisticated decision-making systems. They allow you to regulate the flow of your program, increasing its versatility and interactivity.

In this Python tutorial, we'll look at the if-else statement, covering what it is, how it works, and when to use it. We'll also look at the if-else statement in Python with examples. So, let's start by asking, "What is an if-else statement?"

What is an if-else statement?

• Python's decision-making depends mainly on if-else expressions.
• They define a structure for executing distinct code blocks based on whether a given condition is true or false.
• Consider your program as a road with forks; if-else statements serve as those forks, directing the program's progress based on the conditions encountered.

For example, if you're developing a weather app, you could use an if-else expression to decide whether to suggest an umbrella. The requirement would be: "Is it raining?" If true, the code recommends bringing an umbrella; if false, it may suggest sunglasses.

Types of Control Flow in Python

1. Python If Statement
2. Python If Else Statement
3. Python Nested If Statement
4. Python Elif
5. Ternary Statement | Short Hand If Else Statement

Python If Statement

The if statement is a basic decision-making expression. It determines whether a specific statement or block of statements will be executed.

Flowchart

Syntax

if condition:
    # code block to execute if condition is True

Example

age = 18

if age >= 18:
    print("You are an adult.")

Output

You are an adult.

Explanation

Python If Else Statement

• The if statement itself indicates that if a condition is true, a block of statements will be executed.
• However, if the condition is false, they will not. However, if we want to do anything else if the condition is false, we can use the else statement together with the if statement in Python to execute a block of code.

Flowchart

Syntax

if condition:
    # code block to execute if condition is True
else:
    # code block to execute if condition is False

Example

current_hour = 15

if current_hour < 12:
    print("Good morning!")
else:
    print("Good afternoon!")

Output

Good afternoon!

Explanation

Python Nested If Statement

if condition1:
    if condition2:
        # code block to execute if both condition1 and condition2 are True
    else:
        # code block to execute if condition1 is True but condition2 is False
else:
    # code block to execute if condition1 is False

score = 85
has_passed_exam = True

if score >= 60:
    if has_passed_exam:
        print("Congratulations! You passed with a score of", score)
    else:
        print("You scored well but did not pass the exam.")
else:
    print("You did not pass. Try again.")

Output

Congratulations! You passed with a score of 85

Explanation

Python Elif / if-else ladder

• In this conditional statement in Python, a user can select from a variety of options. The if statements are examined progressively, from top to bottom.
• When a condition evaluates to True, the related block is executed, while the remaining conditions are skipped.
• If none of the conditions hold, the last else block will be executed.
• It's also called an if-else ladder.

Syntax

if condition1:
    # code block to execute if condition1 is True
elif condition2:
    # code block to execute if condition1 is False and condition2 is True
elif condition3:
    # code block to execute if condition1 and condition2 are False and condition3 is True
else:
    # code block to execute if none of the above conditions are True

Example

score = 78

if score >= 90:
    print("Grade: A")
elif 80 <= score < 90:
    print("Grade: B")
elif 70 <= score < 80:
    print("Grade: C")
elif 60 <= score < 70:
    print("Grade: D")
else:
    print("Grade: F")

Output

Grade: C

Explanation

Example

# Example performance rating
rating = 4.5

# Determine the appraisal feedback using an elif ladder
if rating >= 4.5:
    feedback = "Outstanding performance! Expect a significant raise and bonus."
elif rating >= 3.5:
    feedback = "Great job! You're doing well and can look forward to a good raise."
elif rating >= 2.5:
    feedback = "Satisfactory performance. There’s room for improvement, but you’re on the right track."
elif rating >= 1.5:
    feedback = "Needs improvement. Focus on developing your skills and meeting your goals."
else:
    feedback = "Unsatisfactory performance. Immediate improvement is required."

print(f"Your appraisal feedback: {feedback}")

Output

Your appraisal feedback: Outstanding performance! Expect a significant raise and bonus.

Explanation

Ternary Statement | Short Hand If Else Statement

Syntax

value_if_true if condition else value_if_false

Example

age = 16
status = "Adult" if age >= 18 else "Minor"
print(status)

Output

Minor

Explanation