New to Python? Confused by Booleans? Relax! This guide is here to help you get to grips with Python Booleans in no time. Python Booleans are a fundamental data type used to represent a logical value, either True or False. They are the basis for many of the decisions and calculations your code makes, and understanding how to use them effectively is an essential part of becoming a proficient Python programmer. In this comprehensive guide, we’ll cover everything from what Booleans are, to how to use them in your code. We’ll also explore some of the best practices for working with Python Booleans, so you can write clean and efficient code. So, let’s get started!
What are Python Booleans? #
Booleans are a fundamental data type used to represent a logical value, either True or False. Python has two built-in Boolean data types: True and False. These are reserved words of Python, meaning they cannot be used as identifiers for variables. Before moving on, it’s important to note that Boolean values are different from Boolean expressions. Boolean expressions, as we’ll discuss later, are groups of expressions that evaluate to True or False.
Working with Python Booleans #
When working with Booleans, there are two main things to keep in mind: the difference between the Python data type and the Boolean expression, and how Python evaluates Boolean expressions. With that in mind, we can walk through some core operations with Python Booleans.
Assignments – You can assign True or False to a variable, like so: – You can then check the value of a variable by using a Boolean expression. If the value is True, then the expression evaluates to True. If not, it evaluates to False. – Similarly, you can also use Boolean expressions to assign a value to a variable, like so:
Boolean Operators – To use a Boolean operator, you need to use one of Python’s built-in Boolean data types. You cannot mix Python data types with Boolean data types. Let’s take a look at some of the most common Boolean operators: – These operators return True or False, depending on the values of their operands. For example, the “equal to” operator returns True if both operands are the same. The “not equal to” operator returns True if the operands are different.
If Statements – There are a few variations to the if statement. For example, the if-else statement. In such a statement, you have a Boolean expression followed by an if-else statement. The if-else statement checks if the expression is True, and executes the first block of code. Otherwise, if it is False, it executes the else block of code.
For example: – Let’s break this down. The first line is the Boolean expression. Next, we have a colon, followed by the first block of code, if the expression is True, or the else block of code, if the expression is False. Finally, we close the if statement with a colon, followed by an End If statement.
Boolean Short Circuiting – Boolean short circuiting is a technique you can use to shorten the execution time of your code, saving you both time and memory. Short circuiting occurs when the first Boolean expression in an if-else statement evaluates to True. Because the second expression is never evaluated, the if-else statement skips the second block of code.
Let’s take a look at an example: – In this example, the first Boolean expression checks if the value of var1 is not the same as var2. If the first expression evaluates to True, the if-else statement skips the second expression, and immediately executes the first block of code.
Python Boolean Expressions #
As we saw earlier, Boolean expressions are groups of expressions that evaluate to True or False. This means that Boolean expressions can be either simple expressions, like the following: Or compound expressions, like the following: Let’s now explore the various parts of a Boolean expression to better understand how they work. The AND Operator – The AND operator allows you to combine two Boolean expressions to make a new Boolean expression. All the AND operator does is evaluate both expressions, and return True if both expressions evaluate to True. If either expression evaluates to False, it returns False.
Let’s take a look at an example:
The OR Operator – The OR operator is the opposite of the AND operator. It allows you to combine two Boolean expressions to make a single Boolean expression. All the OR operator does is evaluate both expressions, and return True if either expression evaluates to True. If both expressions evaluate to False, it returns False.
Let’s take a look at an example:
The NOT Operator – The NOT operator changes the value of a Boolean expression. It returns the opposite of the original expression, so if the original expression is True, it returns False, and if the original expression is False, it returns True. Let’s take a look at an example:
Boolean Expressions #
As we saw earlier, Boolean expressions are groups of expressions that evaluate to True or False. We also saw how the AND, OR, and NOT operators work. Now, let’s put all that together and create some Boolean expressions. Let’s start with an example: – In this example, the first expression is 4 > 3, which checks if 4 is greater than 3. If the first expression evaluates to True, the second expression is the OR operator, which checks if the value of first is not equal to the value of second. If both expressions evaluate to True, the overall expression evaluates to True.
Now, let’s try a slightly more complex example: – In this example, we have three expressions. The first is the AND operator, which checks if the value of var1 is not equal to the value of var2. The second is the OR operator, which checks if the value of var3 is not equal to the value of var4. The third is the NOT operator, which is the opposite of the first expression. If all three expressions evaluate to True, the overall expression evaluates to True.
Best Practices for Working with Booleans #
It’s worth noting that Python’s decision-making process is based on the outcome of Boolean expressions. And because Python evaluates every expression, even simple expressions like 4 > 3, your code will run more slowly. This makes it important to write clean and efficient code by following these best practices: – Avoid performing unnecessary operations – avoid performing operations that don’t add value to your code. This includes using Python’s built-in functions to perform simple calculations rather than writing your own expressions.
Use short and simple expressions – shorter and simpler expressions make it easier for Python to evaluate them, speeding up your code and making it more efficient. – Avoid if-else statements – if-else statements are useful when you want to perform two different operations based on a single Boolean expression. However, they also slow down your code, so try to avoid them when possible. – Avoid nested if-else statements – nested if-else statements make your code difficult to read, and unnecessary difficult for Python to interpret.
Python If-Else Statements #
As we saw earlier, the if-else statement allows you to execute two different blocks of code based on the outcome of a single Boolean expression. There are a few things to keep in mind when using if-else statements: – The first line is the Boolean expression. Next, we have a colon, followed by the first block of code, if the expression is True, or the else block of code, if the expression is False. Finally, we close the if statement with a colon, followed by an End If statement. – This example checks if the value of var1 is not equal to the value of var2. If the expression evaluates to True, the first block of code executes. Otherwise, the else block of code executes.
Python Boolean Short Circuiting #
As we saw earlier, Boolean short circuiting is a technique you can use to shorten the execution time of your code, saving you both time and memory. Short circuiting occurs when the first Boolean expression in an if-else statement evaluates to True. Because the second expression is never evaluated, the if-else statement skips the second block of code. Let’s take a look at an example: – In this example,
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