Python Control Structures: Making Decisions in Your Code

Control structures are an essential part of programming as they allow you to control the flow of your code. They allow you to create conditions, loops, and branching statements that allow your code to make decisions and execute different blocks of code based on those decisions. In this article, we will explore the different control structures available in Python and how you can use them to make decisions in your code.

If Statements

If statements are the most basic control structure in Python. They allow you to execute a block of code only if a certain condition is true. The syntax for an if statement is as follows:

if condition:
    # code to execute if condition is true

You can also include an else clause to specify a block of code to execute if the condition is not true:

if condition:
    # code to execute if condition is true
else:
    # code to execute if condition is false

You can also use elif clauses to specify additional conditions to check:

if condition1:
    # code to execute if condition1 is true
elif condition2:
    # code to execute if condition1 is false and condition2 is true
else:
    # code to execute if condition1 and condition2 are both false

Here is an example of an if statement in action:

x = 5
if x > 0:
    print("x is positive")
else:
    print("x is not positive")

This code will print "x is positive" to the console because the condition x > 0 is true.

Loops

Loops allow you to repeat a block of code multiple times. There are two types of loops in Python: for loops and while loops.

For Loops

For loops are used to iterate over a sequence of items, such as a list or a string. The syntax for a for loop is as follows:

for item in sequence:
    # code to execute for each item in the sequence

Here is an example of a for loop that iterates over a list of numbers and prints out each number:

numbers = [1, 2, 3, 4, 5]
for number in numbers:
    print(number)

This code will print the numbers 1 through 5 to the console.

While Loops

While loops execute a block of code as long as a certain condition is true. The syntax for a while loop is as follows:

while condition:
    # code to execute while condition is true

Here is an example of a while loop that counts down from 10 and prints out each number:

count = 10
while count > 0:
    print(count)
    count -= 1

This code will print the numbers 10 through 1 to the console.

It is important to make sure that your while loop has a way to end, or it will become an infinite loop and your code will run indefinitely.

Break and Continue

You can use the break and continue statements to alter the flow of a loop. The break statement will exit the loop and move on to the next line of code outside of the loop. The continue statement will skip the rest of the current iteration and move on to the next one.