Python Numeric and String variables

In this article, I will be covering Python numeric and String variables

Python Numeric and String Variables Introduction

Unlike Java, in Python, variables do not have a data type. You just need to specify a variable name. Also, unlike Java, you do not need to declare a variable to be of a particular data type. Python automatically allocates memory to a variable the moment you assign it a value.

Creating a variable

In order to create a variable, you just need to specify the variable name, followed by the assignment operator (=) followed by the value. This automatically allocates memory to the variable based on the data type of the assigned value.

The following code demonstrates this:

i=10

This code declares the variable i and assigns the value 10 to it.

Python Numeric Variables

You can create numeric variables by simply assigning a number to the variable name. Python supports storing whole numbers and decimal numbers.

The following code demonstrates this:

a = 10
b = 100.5

This code creates the variables ‘a‘, ‘b‘

The variable ‘a‘ is of integer type with the value ‘10‘

The variable ‘b‘ is of decimal type with the value 100.5

Python String Variables

You can create String variables by simply assigning a String value to the variable name. The String variable can be enclosed either in single quotes or double quotes. The following code demonstrates this:

c = 'Hello'
d = "world"

This code creates the variables ‘c‘, ‘d‘

The variable ‘c‘ is a String variable with the value ‘Hello‘

The variable ‘d‘ is also a String variable with the value ‘World‘.

Python also supports a number of String operations. You can check out my Python String operations article to know more.

Assigning Multiple Values

Python allows you to assign multiple values to variables at once. The following code demonstrates this:

a,b=200
c=d=e=10.5
f,g=1,'Hello'

a,b are assigned the value 200

c,d,e are assigned the value 10.5

f is assigned the value 1 and g is assigned the value Hello

Changing Data Type

You can change the data type even after assigning a value to it.  So you can do the following:

i=10
i='Hello'

This code first assigns the value 10 to the variable i. It then assigns the value ‘Hello‘

Variable Naming Rules

Python variable names must follow the following rules:

• It cannot start with a number, it must start with a letter or the underscore character
• It can only contain alpha-numeric characters and underscores

More Variables

In addition, Python supports variables of the following types:

• Lists
• Tuples
• Dictionary

You can click the links above to understand more about these types.

Further Learning

The Python Masterclass
Everything you need to know about Python
Python for beginners
Python for finance

Conclusion

In this article, I covered how Python variables work and Python Numeric and String variables.