Python Conditional Statements Explained

Questions and Answers

What keyword is used in Python to express the most basic conditional statement?

What does the `elif` keyword stand for in Python conditional statements?

else if

When does the code block under the `else` statement execute?

When none of the preceding conditions are satisfied

In Python, what happens if the condition in an `if` statement evaluates to `False`?

<p>No code block is executed</p> Signup and view all the answers

Which keyword can be used to handle multiple conditions in Python conditional statements?

<p>elif</p> Signup and view all the answers

Study Notes

Conditional Statements in Python

In programming, conditional statements are used to make decisions based on specified conditions. They allow you to control the flow of your program depending on certain criteria. In Python, these conditional statements are expressed using if, elif, and else keywords. Here's how they work:

The `if` Statement

The most basic conditional statement is the if statement. It checks whether the condition within parentheses evaluates to either True or False. If it does evaluate to True, the block of code indented under the if statement will execute. For example:

x = 5
y = 6

if x > y: # True
    print("x is greater than y")

If x is indeed greater than y, the string message "x is greater than y" would be printed.

The `elif` Statement

Sometimes there might be multiple conditions to check. In this case, we can use the elif keyword. This stands for 'else if'. Just like in the above example with the if statement, additional conditions can be added after the initial test fails. Continuing from our previous example:

x = 5
y = 6

if x > y: # False
    print("x is greater than y")
elif x < y: # True
    print("x is less than y")

Here, when the first condition isn't met, the second condition is checked, and its associated action is taken.

The `else` Statement

Finally, there's also an else statement that executes only when none of the preceding conditions have been satisfied. Adding an else clause to the above examples would result in the following code:

x = 5
y = 6

if x > y: # False
    print("x is greater than y")
elif x < y: # True
    print("x is less than y")
else: # False
    print("x equals y")

Here, since neither the if nor the elif conditions were met, the final else statement gets executed, printing "x equals y".

In summary, Python's conditional statements allow you to structure software applications by making them responsive to different scenarios. As you learn more about flows of execution and branching logic, you'll find yourself writing more sophisticated programs that respond dynamically to real-world situations.