“or” Keyword in Python: Combining Conditions

Python is a powerful programming language that is highly regarded for its simple syntax, readability, and ease of use. One of the most fundamental concepts in programming is the use of conditions to control the flow of a program. In Python, the “or” keyword is used to combine conditions, allowing you to create more complex and powerful logical expressions. In this tutorial, we will explore the “or” keyword in Python and show you how to use it to combine conditions in your programs.

What is the “or” Keyword in Python?

The “or” keyword is a logical operator in Python that is used to combine two or more conditions. It is typically used in an if statement as a way to check if one or more conditions are true. The “or” keyword checks the first condition, and if it is false, it moves on to the next condition, and so on until it finds a condition that is true. If it finds a true condition, it executes the if statement. If it does not find a true condition, it skips the if statement completely.

The syntax for using the “or” keyword in Python is as follows:

if condition1 or condition2:
    # Do something if either condition1 or condition2 is true

Let’s take a look at some examples to see how the “or” keyword can be used to combine conditions in Python.

Example 1: Using “or” to Check If a Value is Within a Range

Suppose you have a program that asks the user to input a number, and you want to check if that number is between 1 and 10. You could use the “or” keyword to combine two conditions: one to check if the number is greater than or equal to 1, and one to check if the number is less than or equal to 10. Here is the code:

number = int(input("Enter a number between 1 and 10: "))

if number >= 1 or number <= 10:
    print("Your number is within the range of 1 to 10.")
else:
    print("Your number is not within the range of 1 to 10.")

In this example, if the user enters a number that is greater than or equal to 1, or less than or equal to 10, the program will print the message “Your number is within the range of 1 to 10.” Otherwise, it will print “Your number is not within the range of 1 to 10.”

Let’s try running this code:

Enter a number between 1 and 10: 6
Your number is within the range of 1 to 10.

Enter a number between 1 and 10: 11
Your number is not within the range of 1 to 10.

Example 2: Using “or” to Check If a String Contains Certain Characters

Suppose you have a program that asks the user to enter a password, and you want to check if the password contains at least one uppercase letter or at least one digit. You could use the “or” keyword to combine two conditions: one to check if the string contains at least one uppercase letter, and one to check if the string contains at least one digit. Here is the code:

password = input("Enter a password: ")

if any(c.isupper() for c in password) or any(c.isdigit() for c in password):
    print("Your password is valid.")
else:
    print("Your password is not valid. It must contain at least one uppercase letter or one digit.")

In this example, we use the any() function to check each character in the string to see if it is an uppercase letter or a digit. If the string contains at least one uppercase letter or at least one digit, the program will print the message “Your password is valid.” Otherwise, it will print “Your password is not valid. It must contain at least one uppercase letter or one digit.”

Let’s try running this code:

Enter a password: HelloWorld
Your password is valid.

Enter a password: helloworld
Your password is not valid. It must contain at least one uppercase letter or one digit.

Example 3: Using “or” with if, elif and else Statements

The “or” keyword can also be used with if, elif and else statements to create more complicated logical expressions. Here is an example:

number = 15

if number < 10 or number > 20:
    print("The number is outside the range of 10 to 20.")
elif number <= 15:
    print("The number is less than or equal to 12.")
else:
    print("The number is greater than 15.")

In this example, we use the “or” keyword to check if the number is less than 10 or greater than 20. If it is, we print the message “The number is outside the range of 10 to 20.” If it is not, we move on to the next condition, which is an elif statement that checks if the number is less than or equal to 15. If it is, we print the message “The number is less than or equal to 12.” If it is not, we print the message “The number is greater than 15.”

Let’s try running this code:

The number is greater than 15.

Conclusion

The “or” keyword in Python is a powerful tool that allows you to create more complex and powerful logical expressions in your programs. By combining conditions with “or”, you can create programs that are more flexible and responsive to user input. We hope this tutorial has given you a better understanding of the “or” keyword in Python and how it can be used in your programs.