Python Crash Course for Beginners | Python Variables
Python is a powerful and popular programming language that is used for a wide range of applications such as web development, data analysis, and machine learning. One of the most fundamental concepts in Python is variables. In this article, we will discuss what variables are in Python, how to use them, and provide coding examples to illustrate their usage.
What are variables in Python?
A variable is a named location in memory that is used to store data in a Python program. You can think of a variable as a container that holds a value. The value of a variable can be changed during the program’s execution. Variables can hold different types of data such as numbers, strings, and lists.
How to create variables in Python?
In Python, creating a variable is very easy. You simply give it a name and assign a value to it using the assignment operator (=). Here is an example:
x = 5
In this example, we have created a variable named x
and assigned it the value of 5
. The equal sign (=) is the assignment operator and it is used to assign a value to a variable.
You can also assign values to multiple variables at once using the comma (,) operator. Here is an example:
x, y, z = 5, 10, 15
In this example, we have created three variables named x
, y
, and z
and assigned them the values of 5
, 10
, and 15
respectively.
How to access variables in Python?
Once a variable is created, you can access its value by using its name. Here is an example:
x = 5
print(x)
In this example, we have created a variable named x
and assigned it the value of 5
. We then used the print()
function to print the value of the variable to the console. The output of this program will be 5
.
You can also use variables in expressions. Here is an example:
x = 5
y = 10
z = x + y
print(z)
In this example, we have created three variables named x
, y
, and z
. We assigned the values of 5
and 10
to x
and y
respectively. We then used the +
operator to add the values of x
and y
and assigned the result to z
. We then printed the value of z
to the console. The output of this program will be 15
.
Variable naming rules in Python
In Python, variable names must follow some rules:
- A variable name can only contain letters, digits, and underscores (_).
- A variable name must start with a letter or an underscore.
- A variable name cannot start with a digit.
- Variable names are case-sensitive. For example,
x
andX
are different variables.
Here are some examples of valid variable names in Python:
my_variable
myVariable
my_variable_1
x
x1
Here are some examples of invalid variable names in Python:
1variable
my-variable
my variable
In summary, variables are a fundamental concept in Python programming. They are used to store and manipulate data in a program. In this article, we discussed how to create variables in Python, how to access their values, and the naming rules for variables. By understanding these concepts and practicing with coding examples, you can become proficient in using variables in your Python programs.
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