The main objective of this tutorial is to enlighten the concept of data types and their classification in the python programming language.
Data type in python can be defined as a kind of data that a variable or an object can hold and perform operations based on the data. It helps to determine the type and size of the data a programmer intends to interpret.
Being an interpretable programming language python implicitly assigns the data type to a variable. No specific declaration is required. Based on the data type, memory is allocated which means the space required for the data and for its operation is dynamically secured in memory.
age = 17 #age is a variable of datatype number
first_name = ‘Robert’ #first_name is a variable of datatype string
X = 21.5 #X is a variable of datatype float
In the Python programming language, Data types are broadly classified into 7 built types namely numeric, text sequence, sequence, mapping, set, boolean, and binary sequences. Each type is again classified into basic data types based on their unique feature.
In python, when a variable is assigned with a numeric value then it comes under the Python Number Datatype. A number datatype comprises of an integer value, float value, and a complex type value which are precisely stated as
Int is a number data type in python that comprises both positive and negative whole numbers and zero. It does not hold the fractional part.
Float, also known as floating-point number comprises of signed fractional numbers.
Complex numbers are numbers comprised of a real part and an imaginary part to take the form a+ib where a and b are real numbers and b is associated with an imaginary unit, i.
i = 10 #i is a variable of type int
print("i = ",i)
f = 10.55 #f is a variable of type float
print("f = ",f)
C =-5-6i #C is a variable of type Complex
print("C =",C)
Output:
i = 10 f = 10.55 C = -5-6i
In the Python programming language, the string data type is a text sequence-based datatype. A string is usually a finite series or sequence of Unicode characters bounded either in double quotes or single quotes. To represent a multiple-line string we can use either ‘ ‘ ‘ or “””.
Str1 = ' First String '
Str2 = " Second String "
Str3 = ' ' ' Multiple line …
…String example ' ' '
print(str1)
print(str2)
print(str3)
Output:
First String Second String Mutliple line… …String example
On the ground of sequences, Python data types are classified into three. They are
A list can be defined as a well-ordered collection of values that are mutable. In python, values in a list are separated using commas and are enclosed in a square bracket [ ].
Python tuples are also a well-ordered collection of values that are immutable in nature. In python, values in a tuple are separated using commas and are enclosed in a round bracket or parenthesis ().
Python range type is used to represent a fixed series of numbers and also used in for loop and while loop to denote fixed iterations.
colorlist = ['violet', 'yellow', 'blue', 'green', 'indigo']
colourtupe = ('violet', 'yellow', 'blue', 'green', 'indigo')
x=range(10)
y=list(range(10))
print( "List of colours :",colorlist)
print( "Tuple of colours :",colorlist)
print(x)
print('List values in range of 10 :',y)
Output:
List of colours : ['violet', 'yellow', 'blue', 'green', 'indigo']
Tuple of colours : ('violet', 'yellow', 'blue', 'green', 'indigo')
range(0, 10)
List values in range of 10 : [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
In the Python programming language, a set entity is an unordered collection of unique hashable entities. Two built-in set types are:
Python set is a group of distinctive items which are neither indexed nor ordered and are mutable. Set values are not hashable. Python sets are usually surrounded by curly braces { }, separated using commas.
Python Frozenset contains a collection of distinct objects which are immutable and hashable in nature.
colorset = {'violet','indigo','blue','green','yellow'}
print("Set of colours are :",colorset)
flowerset =frozenset({'jasmine','marigold','sunflower'})
print("Frozen set of flowers are:",flowerset)
Output:
Set of colours are : {'violet', 'yellow', 'blue', 'green', 'indigo'}
Frozen set of flowers are: frozenset({'jasmine', 'marigold', 'sunflower'})
In the Python programming language, a dictionary is a collection of combination pairs Key and Values which are indexed, mutable but not in order. Combination pairs Key: Values are encapsulated in curly braces { } and can be of any data type. Values are extracted using Key and the opposite way is not possible.
D = {
"Flower":"Rose",
"Fruit":"Cherry",
"Age":20
}
A=D['Age']
F=D["Flower"]
print(D)
print("Age is ",A)
print("Flower is",F)
Output:
{'Flower': 'Rose', 'Fruit': 'Cherry', 'Age': 20}
Age is 20
Flower is Rose
Boolean Datatype is a datatype which holds one of the possible value, True(1) or False(0).
In python, Boolean datatype returns the truth value of an expression using the python keywords, True or False.
Boolean is typically used to evaluate an expression. The expression can be logical, arithmetic, etc which you will learn in the succeeding tutorial.
a = 100
b = 200
print(a > b)
print(a < b)
print(a == b)
print(a != b)
if a < b:
print(a,'is less than', b)
else:
print(a,' is greater than',b)
Output:
False True False True 100 is less than 200
Binary sequence Datatypes are categorized into three types in the python programming language. They are
Bytes are primarily built-in data types used to manage binary data. bytes entities are unchangeable series of single bytes.
bytearray is another primary built-in datatype used to control binary data. Unlike bytes, bytearray is mutable in nature.
memoryview is used in python code to acquire the internal data of a specific object. It also supports bytes and bytearray with the help of buffer protocol.
a=b"Python" #bytes datatype
x= bytes(10) #bytes datatype
y=bytearray(5) #bytearray
z=memoryview(bytes(10)) #memoryview
print('a = ',a)
print('x = ',x)
print('y = ',y)
print('z = ',z)
Output:
a = b'Python' x = b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00' y = bytearray(b'\x00\x00\x00\x00\x00') z = memory at 0x034D8268
The table below shows the common factors and comparison of datatypes over the factors.
From the table, we can infer the following points.
We have already learned that python is a highly type-based programming language. Each data has its own type. In order to retrieve the type of data, we use a built-in function,type( ) function. type(object) function returns the specific object type on passing a single argument to the function
Syntax of the type function :type(object)
i = type(10)
print(i) #returns <class ‘int’>
f = type(10.55)
print(f) #returns <class ‘float’>
STR = type(‘Welcome’)
print(STR) #returns <class ‘str’>
List_ex =type [1,2,3,4,5,6]
print(List_ex) #returns <class ‘list’>
Set_ex =type({5,3,1,2})
Print(Set_ex) #returns <class ‘set’>
D = {
“Flower” : ”Rose“
}
Print(type(D)) #returns <class ‘dict’>
Output:
<class ‘int’> <class ‘float’> <class ‘str’> <class ‘list’> <class ‘set’> <class ‘dict’>
