Data Types
Data type specifies the type of value a variable requires to do various operations without causing an error. By default, Python provides the following built-in data types:
Numeric data: int, float, complex
- int: 3, -8, 0
- float: 7.349, -9.0, 0.0000001
- complex: 6 + 2i
More on numeric data types in the number chapter.
Text data: str
- str: "Hello World!!!", "Python Programming"
Boolean data:
Boolean data consists of values True
or False
.
Sequenced data: list, tuple, range
list: A list is an ordered collection of data with elements separated by a comma and enclosed within square brackets. Lists are mutable and can be modified after creation.
Example:
list1 = [8, 2.3, [-4, 5], ["apple", "banana"]]
print(list1)
Output:
[8, 2.3, [-4, 5], ['apple', 'banana']]
tuple: A tuple is an ordered collection of data with elements separated by a comma and enclosed within parentheses. Tuples are immutable and cannot be modified after creation.
Example:
tuple1 = (("parrot", "sparrow"), ("Lion", "Tiger"))
print(tuple1)
Output:
(('parrot', 'sparrow'), ('Lion', 'Tiger'))
range: Returns a sequence of numbers as specified by the user. If not specified by the user, it starts from 0 by default and increments by 1.
Example:
sequence1 = range(4, 14, 2)
for i in sequence1:
print(i)
Output:
4
6
8
10
12
Mapped data: dict
dict: A dictionary is an unordered collection of data containing a key:value pair. The key:value pairs are enclosed within curly brackets.
Example:
dict1 = {"name": "Sakshi", "age": 20, "canVote": True}
print(dict1)
Output:
{'name': 'Sakshi', 'age': 20, 'canVote': True}
Binary data: bytes, bytearray, memoryview
bytes: bytes()
function is used to convert objects into byte objects, or create an empty bytes object of the specified size.
Example:
# Converting string to bytes
str1 = "This is a string"
arr1 = bytes(str1, 'utf-8')
print(arr1)
arr2 = bytes(str1, 'utf-16')
print(arr2)
# Creating bytes of given size
bytestr = bytes(4)
print(bytestr)
Output:
b'This is a string'
b'\xff\xfeT\x00h\x00i\x00s\x00 \x00i\x00s\x00 \x00a\x00 \x00s\x00t\x00r\x00i\x00n\x00g\x00'
b'\x00\x00\x00\x00'
bytearray: bytearray()
function is used to convert objects into bytearray objects, or create an empty bytearray object of the specified size.
Example:
# Converting string to bytes
str1 = "This is a string"
arr1 = bytearray(str1, 'utf-8')
print(arr1)
arr2 = bytearray(str1, 'utf-16')
print(arr2)
# Creating bytes of given size
bytestr = bytearray(4)
print(bytestr)
Output:
bytearray(b'This is a string')
bytearray(b'\xff\xfeT\x00h\x00i\x00s\x00 \x00i\x00s\x00 \x00a\x00 \x00s\x00t\x00r\x00i\x00n\x00g\x00')
bytearray(b'\x00\x00\x00\x00')
memoryview: memoryview()
function returns a memory view object from a specified object.
Example:
str1 = bytes("home", "utf-8")
memoryviewstr = memoryview(str1)
print(list(memoryviewstr[0:]))
Output:
[104, 111, 109, 101]
Set data:
Set is an unordered collection of elements in which no element is repeated. The elements of sets are separated by a comma and contained within curly braces.
Example:
set1 = {4, -5, 8, 3, 2.9}
print(set1)
Output:
{2.9, 3, 4, 8, -5}
None:
None is used to define a null value. When we assign a None value to a variable, we are essentially resetting it to its original empty state, which is not the same as zero, an empty string, or a False value.
Example:
state = None
print(type(state))
Output:
<class 'NoneType'>