Python Data Types

Python Data types are the classification or categorization of data items. It represents the kind of value that tells what operations can be performed on a particular data. Since everything is an object in Python programming, Python data types are classes and variables are instances (objects) of these classes. The following are the standard or built-in data types in Python:

• Numeric

• Sequence Type

• Boolean

• Set

• Dictionary

• Binary Types( memoryview, bytearray, bytes)

What is Python Data Types?

To define the values ​​of various data types of Python and check their data types we use the type() function. Consider the following examples.

This code assigns variable ‘x’ different values of various Python data types. It covers string, integer, float, complex, list, tuple, range, dictionary, set, frozenset, boolean, bytes, bytearray, memoryview, and the special value ‘None’ successively. Each assignment replaces the previous value, making ‘x’ take on the data type and value of the most recent assignment.

Python3

x = "Hello World"
x = 50
x = 60.5
x = 3j
x = ["geeks", "for", "geeks"]
x = ("geeks", "for", "geeks")
x = range(10)
x = {"name": "Suraj", "age": 24}
x = {"geeks", "for", "geeks"}
x = frozenset({"geeks", "for", "geeks"})
x = True
x = b"Geeks"
x = bytearray(4)
x = memoryview(bytes(6))
x = None

1. Numeric Data Types in Python

The numeric data type in Python represents the data that has a numeric value. A numeric value can be an integer, a floating number, or even a complex number. These values are defined as Python int, Python float, and Python complex classes in Python.

• Integers – This value is represented by int class. It contains positive or negative whole numbers (without fractions or decimals). In Python, there is no limit to how long an integer value can be.

• Float – This value is represented by the float class. It is a real number with a floating-point representation. It is specified by a decimal point. Optionally, the character e or E followed by a positive or negative integer may be appended to specify scientific notation.

• Complex Numbers – A complex number is represented by a complex class. It is specified as (real part) + (imaginary part)j. For example – 2+3j

Note – type() function is used to determine the type of Python data type.

Example: This code demonstrates how to determine the data type of variables in Python using the type() function. It prints the data types of three variables: a (integer), b (float), and c (complex). The output shows the respective data type Python for each variable.

Python3

a = 5
print("Type of a: ", type(a))

b = 5.0
print("\nType of b: ", type(b))

c = 2 + 4j
print("\nType of c: ", type(c))

Output:

Type of a:  <class 'int'>
Type of b:  <class 'float'>
Type of c:  <class 'complex'>

2. Sequence Data Types in Python

The sequence Data Type in Python is the ordered collection of similar or different Python data types. Sequences allow storing of multiple values in an organized and efficient fashion. There are several sequence data types of Python:

3. Boolean Data Type in Python

Python Data type with one of the two built-in values, True or False. Boolean objects that are equal to True are truthy (true), and those equal to False are falsy (false). However non-Boolean objects can be evaluated in a Boolean context as well and determined to be true or false. It is denoted by the class bool.

Note – True and False with capital ‘T’ and ‘F’ are valid booleans otherwise python will throw an error.

Example: The first two lines will print the type of the boolean values True and False, which is <class ‘bool’>. The third line will cause an error, because true is not a valid keyword in Python. Python is case-sensitive, which means it distinguishes between uppercase and lowercase letters. You need to capitalize the first letter of true to make it a boolean value.

Python3

print(type(True))
print(type(False))

print(type(true))

Output:

<class 'bool'>
<class 'bool'>

Traceback (most recent call last):
  File "/home/7e8862763fb66153d70824099d4f5fb7.py", line 8, in 
    print(type(true))
NameError: name 'true' is not defined

4. Set Data Type in Python

In Python Data Types, a Set is an unordered collection of data types that is iterable, mutable, and has no duplicate elements. The order of elements in a set is undefined though it may consist of various elements.

Create a Set in Python

Sets can be created by using the built-in set() function with an iterable object or a sequence by placing the sequence inside curly braces, separated by a ‘comma’. The type of elements in a set need not be the same, various mixed-up data type values can also be passed to the set.

Example: The code is an example of how to create sets using different types of values, such as strings, lists, and mixed values

Python3

set1 = set()
print("Initial blank Set: ")
print(set1)
set1 = set("GeeksForGeeks")
print("\nSet with the use of String: ")
print(set1)
set1 = set(["Geeks", "For", "Geeks"])
print("\nSet with the use of List: ")
print(set1)
set1 = set([1, 2, 'Geeks', 4, 'For', 6, 'Geeks'])
print("\nSet with the use of Mixed Values")
print(set1)

Output:

Initial blank Set: 
set()
Set with the use of String: 
{'F', 'o', 'G', 's', 'r', 'k', 'e'}
Set with the use of List: 
{'Geeks', 'For'}
Set with the use of Mixed Values
{1, 2, 4, 6, 'Geeks', 'For'}

Access Set Items

Set items cannot be accessed by referring to an index, since sets are unordered the items have no index. But you can loop through the set items using a for loop, or ask if a specified value is present in a set, by using the in the keyword.

Example: This Python code creates a set named set1 with the values “Geeks”, “For” and “Geeks”. The code then prints the initial set, the elements of the set in a loop, and checks if the value “Geeks” is in the set using the ‘in’ operator

Python3

set1 = set(["Geeks", "For", "Geeks"])
print("\nInitial set")
print(set1)
print("\nElements of set: ")
for i in set1:
    print(i, end=" ")
print("Geeks" in set1)

Output:

Initial set: 
{'Geeks', 'For'}
Elements of set: 
Geeks For 
True

Note – To know more about sets, refer to Python Sets.

5. Dictionary Data Type in Python

A dictionary in Python is an unordered collection of data values, used to store data values like a map, unlike other Python Data Types that hold only a single value as an element, a Dictionary holds a key: value pair. Key-value is provided in the dictionary to make it more optimized. Each key-value pair in a Dictionary is separated by a colon : , whereas each key is separated by a ‘comma’.

Create a Dictionary in Python

In Python, a Dictionary can be created by placing a sequence of elements within curly {} braces, separated by ‘comma’. Values in a dictionary can be of any datatype and can be duplicated, whereas keys can’t be repeated and must be immutable. The dictionary can also be created by the built-in function dict(). An empty dictionary can be created by just placing it in curly braces{}. Note – Dictionary keys are case sensitive, the same name but different cases of Key will be treated distinctly.

Example: This code creates and prints a variety of dictionaries. The first dictionary is empty. The second dictionary has integer keys and string values. The third dictionary has mixed keys, with one string key and one integer key. The fourth dictionary is created using the dict() function, and the fifth dictionary is created using the [(key, value)] syntax

Python3

Dict = {}
print("Empty Dictionary: ")
print(Dict)
Dict = {1: 'Geeks', 2: 'For', 3: 'Geeks'}
print("\nDictionary with the use of Integer Keys: ")
print(Dict)
Dict = {'Name': 'Geeks', 1: [1, 2, 3, 4]}
print("\nDictionary with the use of Mixed Keys: ")
print(Dict)
Dict = dict({1: 'Geeks', 2: 'For', 3: 'Geeks'})
print("\nDictionary with the use of dict(): ")
print(Dict)
Dict = dict([(1, 'Geeks'), (2, 'For')])
print("\nDictionary with each item as a pair: ")
print(Dict)

Output:

Empty Dictionary: 
{}
Dictionary with the use of Integer Keys: 
{1: 'Geeks', 2: 'For', 3: 'Geeks'}
Dictionary with the use of Mixed Keys: 
{1: [1, 2, 3, 4], 'Name': 'Geeks'}
Dictionary with the use of dict(): 
{1: 'Geeks', 2: 'For', 3: 'Geeks'}
Dictionary with each item as a pair: 
{1: 'Geeks', 2: 'For'}