Error Handling in Python – try except

In this video, we’ll delve into the intricacies of try…except blocks, handling specific exceptions like ZeroDivisionError or IndexError, and utilizing try with else.

What You’ll Learn:

try…except Block: Understand the basics of handling exceptions.
Handling Specific Exceptions: Learn how to manage specific errors like ZeroDivisionError and IndexError effectively.
Using try with else: Discover how to execute code when no exceptions are raised, making your programs more robust and error-proof.

Whether you’re a beginner or an experienced Python developer, mastering error handling is crucial.

Tutorial Video

Python Code

Error handling is a fundamental aspect of writing robust and reliable code.
As developers, we encounter unexpected situations—such as division by zero, out-of-bounds array access, or invalid input—more often than we’d like.
Python provides powerful tools to gracefully handle these exceptions and prevent our programs from crashing.

Basic Exception Handling:

In Python, we use the try…except block to handle exceptions.
The try block contains the potentially problematic code. If an exception occurs (like division by zero), the except block catches it and executes the specified statements

numerator   = 10
denominator = 0

try:
    # Code that may cause an exception
    numerator = 10
    denominator = 0
    result = numerator / denominator
    print(result)
except:
    # Code to run when an exception occurs
    print("Error: Denominator cannot be 0.")

Handling Specific Exceptions:

You can handle different exceptions differently using multiple except blocks.
In this case, we handle ZeroDivisionError and IndexError separately. If an index out of bounds occurs, the IndexError block is executed

try:
    even_numbers = [2, 4, 6, 8]
    print(even_numbers[5])  # Accessing index 5 (out of bounds)
except ZeroDivisionError:
    print("Denominator cannot be 0.")
except IndexError:
    print("Index Out of Bound.")

Using try with else:

Sometimes, we want to run code only if the try block runs without errors. The else keyword helps achieve this
If the input is an even number, the reciprocal is computed and displayed. Otherwise, the error message is shown

num = 3

try:
    assert num % 2 == 0  # Check if even
except:
    print("Not an even number!")
else:
    reciprocal = 1 / num
    print(reciprocal)

Example 1: Dividing two numbers

# Function to divide two numbers
def divide_numbers(num1, num2):
    try:
        result = num1 / num2
        return result
    except ZeroDivisionError as e:
        print(f"Error: {e} - Cannot divide by zero.")
    except TypeError as e:
        print(f"Error: {e} - Please provide valid numbers.")
    except Exception as e:
        print(f"Error: {e} - An unexpected error occurred.")

# Example usage of the divide_numbers function
print("Example 1: Dividing two numbers")
print(divide_numbers(10, 2))  
print(divide_numbers(10, 0))  
print(divide_numbers('10', 2))

Example 2: Opening a file

# Function to divide two numbers
def divide_numbers(num1, num2):
    try:
        result = num1 / num2
        return result
    except ZeroDivisionError as e:
        print(f"Error: {e} - Cannot divide by zero.")
    except TypeError as e:
        print(f"Error: {e} - Please provide valid numbers.")
    except Exception as e:
        print(f"Error: {e} - An unexpected error occurred.")

# Example usage of the divide_numbers function
print("Example 1: Dividing two numbers")
print(divide_numbers(10, 2))  
print(divide_numbers(10, 0))  
print(divide_numbers('10', 2))