# How to Square a List in Python

In this Python tutorial, I will show you how to square a list in Python with examples.

Squaring a number simply means multiplying that number by itself. So, for example, the square of 2 is 4 (2 * 2), the square of 3 is 9 (3 * 3), and so on.

## Square a list of numbers in Python

Now, let us check different ways to square a list of numbers in Python.

There are several ways to square a list of numbers in Python.

### Method 1: Using a for loop

You can use a for loop to iterate over the list and square each number in Python. Here’s how:

``````my_list = [1, 2, 3, 4, 5]
squared_list = []

for number in my_list:
squared_list.append(number**2)

print(squared_list)``````

In this code, `number**2` is where the squaring happens. The `**` is Python’s exponentiation operator.

Output:

``[1, 4, 9, 16, 25]``

You can see the output when I executed the Python program.

### Method 2: Using list comprehension

List comprehension is a concise way to create lists based on existing lists. Here’s how to use it to square a list:

``````my_list = [1, 2, 3, 4, 5]
squared_list = [number**2 for number in my_list]

print(squared_list)``````

Output:

``[1, 4, 9, 16, 25]``

As you can see, this does the same thing as the for loop example, but in a more concise way.

Check out the below output of the code.

### Method 3: Using the map function

The map function in Python applies a given function to each item of an iterable (like a list) and returns a list of the results.

``````my_list = [1, 2, 3, 4, 5]
squared_list = list(map(lambda x: x**2, my_list))

print(squared_list)``````

Output:

``[1, 4, 9, 16, 25]``

In this code, `lambda x: x**2` is a small anonymous function that squares its input.

Another example of having negative numbers:

``````my_list = [-1, -2, -3, -4, -5]
squared_list = list(map(lambda x: x**2, my_list))

print(squared_list)``````

Output:

``[1, 4, 9, 16, 25]``

In this example, the Python list contains negative numbers. When a negative number is squared, the result is positive.

Below you can check the Python code execution.

## How to square a number in Python

Now, let us look at a simple example of how to square a number in Python.

In Python, you can square a number using the exponentiation operator `**`. This operator raises the number on its left to the power of the number on its right. Here’s the syntax:

``number_squared = number ** 2``

And here’s a simple example:

``````number = 7
number_squared = number ** 2
print(number_squared)``````

When you run this code, you’ll get the output:

``49``

In this example, the number 7 is squared, so the result is 49. You can replace `7` with any number you want to square.

If you want to create a reusable function to square a number, you can do that like this:

``````def square(number):
return number ** 2

print(square(7))``````

When you run this code, you’ll get the same output:

``49``

In this version of the code, the `square` function takes one argument (the number you want to square), squares it, and returns the result. You can call this function with any number you want to square.

## Conclusion

In this tutorial, we learned about squaring a number in Python. And also we saw different ways how to square a list of numbers in Python.

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