Python Projects for Beginners a ten-Week Bootcamp Approach to Python Programming

Writing Your First Elif Statement

Creating an elif statement is identical to an if statement, with one difference, you use the elif keyword instead. You’re able to have multiple conditions for each elif as well. Let’s try it:

# using the elif conditional statement x, y = 5, 10 if x > y:
print("x is greater") elif x < y: print("x is less")

Go ahead and run that cell. Notice that the output is “x is less”. It checked the initial if statement, but since that returned False, it moved on to the elif conditional statement. That statement returned True and the block of code within it ran.

Checking Multiple Elif Conditions

Having the ability to write multiple decisions based on a single variable is a necessity, which is why elif statements were built. Take the following code, for instance:

# checking more than one elif conditional statement x, y = 5, 10 if x > y:
print("x is greater") elif (x + 10) < y: # checking if 15 is less than 10 print("x is less") elif (x + 5) == y: # checking if 10 is equal to 10 print("equal")

Go ahead and run that cell. The resulting output is “equal”. The first if and elif statements both returned False, but the second elif statement returned True, which is why that block of code ran. You can have as many elifs as you want, but they must be associated with an if statement.
Note Within the conditional, we perform addition, but we wrap it within parenthesis so that it executes the math operation first.

Conditionals Within Conditionals

We’ve gone over how Python uses indentation to separate blocks of code. So far, we’ve only seen one indentation level, but what if we added an if statement within an if statement?

# writing multiple conditionals within each other - multiple block levels x, y, z = 5, 10, 5 if x > y:
print("greater") elif x <= y: if x == z:
print("x is equal to z") # resulting output elif x != z: print("x is not equal to z") # won't get hit

Go ahead and run that cell. The output results in “x is equal to z”. To break it down, the initial if statement returns False, and the next elif statement returns True, so it runs that block. Now inside of that block is another conditional statement, so it checks the first if statement, which returns True, and runs the block of code inside that.