Python - Operators

Python Operators

Python and other programming languages provide different type of operators which are symbols (sometimes called keywords) and used to perform a certain most commonly required operations on one or more operands. Operators allow different operations like addition, subtraction, multiplication, division etc.

Python operatorsare special symbols used to perform specific operations on one or more operands. Thevariables, values, or expressions can be used as operands. For example, Python’s addition operator (+) is used to perform addition operations on two variables, values, or expressions.

The following are some of the terms related toPython operators:

• Unary operators: Python operators that require one operand to perform a specific operation are known as unary operators.
• Binary operators: Python operators that require two operands to perform a specific operation are known as binary operators.
• Operands: Variables, values, or expressions that are used with the operator to perform a specific operation.

Types of Python Operators

Python operators are categorized in the following categories −

• Arithmetic Operators
• Comparison (Relational) Operators
• Assignment Operators
• Logical Operators
• Bitwise Operators
• Membership Operators
• Identity Operators

Let us have a look at all the operators one by one.

Python Arithmetic Operators

Python Arithmetic operatorsare used to perform basic mathematical operations such as addition, subtraction, multiplication, etc.

The following table contains all arithmetic operators with their symbols, names, and examples (assume that the values ofaandbare 10 and 20, respectively) −

OperatorNameExample+Additiona + b = 30-Subtractiona b = -10*Multiplicationa * b = 200/Divisionb / a = 2%Modulusb % a = 0Exponentab =10**20//Floor Division9//2 = 4

Example of Python Arithmetic Operators

a = 21
b = 10
c = 0

c = a + b
print ("a: {} b: {} a+b: {}".format(a,b,c))

c = a - b
print ("a: {} b: {} a-b: {}".format(a,b,c) )

c = a * b
print ("a: {} b: {} a*b: {}".format(a,b,c))

c = a / b
print ("a: {} b: {} a/b: {}".format(a,b,c))

c = a % b
print ("a: {} b: {} a%b: {}".format(a,b,c))

a = 2
b = 3
c = a**b 
print ("a: {} b: {} a**b: {}".format(a,b,c))

a = 10
b = 5
c = a//b 
print ("a: {} b: {} a//b: {}".format(a,b,c))

Output

a: 21 b: 10 a+b: 31
a: 21 b: 10 a-b: 11
a: 21 b: 10 a*b: 210
a: 21 b: 10 a/b: 2.1
a: 21 b: 10 a%b: 1
a: 2 b: 3 a**b: 8
a: 10 b: 5 a//b: 2

Python Comparison Operators

Python Comparison operatorscompare the values on either side of them and decide the relation among them. They are also called Relational operators.

The following table contains all comparison operators with their symbols, names, and examples (assume that the values ofaandbare 10 and 20, respectively) −

Example of Python Comparison Operators

a = 21
b = 10
if ( a == b ):
   print ("Line 1 - a is equal to b")
else:
   print ("Line 1 - a is not equal to b")

if ( a != b ):
   print ("Line 2 - a is not equal to b")
else:
   print ("Line 2 - a is equal to b")

if ( a < b ):
   print ("Line 3 - a is less than b" )
else:
   print ("Line 3 - a is not less than b")

if ( a > b ):
   print ("Line 4 - a is greater than b")
else:
   print ("Line 4 - a is not greater than b")

a,b=b,a #values of a and b swapped. a becomes 10, b becomes 21

if ( a <= b ):
   print ("Line 5 - a is either less than or equal to  b")
else:
   print ("Line 5 - a is neither less than nor equal to  b")

if ( b >= a ):
   print ("Line 6 - b is either greater than  or equal to b")
else:
   print ("Line 6 - b is neither greater than  nor equal to b")

Output

Line 1 - a is not equal to b
Line 2 - a is not equal to b
Line 3 - a is not less than b
Line 4 - a is greater than b
Line 5 - a is either less than or equal to  b
Line 6 - b is either greater than  or equal to b

Python Assignment Operators

Python Assignment operatorsare used to assign values to variables. Following is a table which shows all Python assignment operators.

The following table contains all assignment operators with their symbols, names, and examples −

Example of Python Assignment Operators

a = 21
b = 10
c = 0
print ("a: {} b: {} c : {}".format(a,b,c))
c = a + b
print ("a: {}  c = a + b: {}".format(a,c))

c += a
print ("a: {} c += a: {}".format(a,c))

c *= a
print ("a: {} c *= a: {}".format(a,c))

c /= a 
print ("a: {} c /= a : {}".format(a,c))

c  = 2
print ("a: {} b: {} c : {}".format(a,b,c))
c %= a
print ("a: {} c %= a: {}".format(a,c))

c **= a
print ("a: {} c **= a: {}".format(a,c))

c //= a
print ("a: {} c //= a: {}".format(a,c))

Output

a: 21 b: 10 c : 0
a: 21  c = a + b: 31
a: 21 c += a: 52
a: 21 c *= a: 1092
a: 21 c /= a : 52.0
a: 21 b: 10 c : 2
a: 21 c %= a: 2
a: 21 c **= a: 2097152
a: 21 c //= a: 99864

Python Bitwise Operators

Python Bitwise operatorworks on bits and performs bit by bit operation. These operators are used to compare binary numbers.

The following table contains all bitwise operators with their symbols, names, and examples −

Example of Python Bitwise Operators

a = 20            
b = 10            

print ('a=',a,':',bin(a),'b=',b,':',bin(b))
c = 0

c = a & b;        
print ("result of AND is ", c,':',bin(c))

c = a | b;     
print ("result of OR is ", c,':',bin(c))

c = a ^ b;        
print ("result of EXOR is ", c,':',bin(c))

c = ~a;           
print ("result of COMPLEMENT is ", c,':',bin(c))

c = a << 2;       
print ("result of LEFT SHIFT is ", c,':',bin(c))

c = a >> 2;       
print ("result of RIGHT SHIFT is ", c,':',bin(c))

Output

a= 20 : 0b10100 b= 10 : 0b1010
result of AND is  0 : 0b0
result of OR is  30 : 0b11110
result of EXOR is  30 : 0b11110
result of COMPLEMENT is  -21 : -0b10101
result of LEFT SHIFT is  80 : 0b1010000
result of RIGHT SHIFT is  5 : 0b101

Python Logical Operators

Python logical operatorsare used to combile two or more conditions and check the final result. There are following logical operators supported by Python language. Assume variable a holds 10 and variable b holds 20 then

The following table contains all logical operators with their symbols, names, and examples −

OperatorNameExampleandANDa and borORa or bnotNOTnot(a)

Example of Python Logical Operators

var = 5

print(var > 3 and var < 10)
print(var > 3 or var < 4)
print(not (var > 3 and var < 10))

Output

True
True
False

Python Membership Operators

Python’smembership operatorstest for membership in a sequence, such as strings, lists, or tuples.

There are two membership operators as explained below −

OperatorDescriptionExampleinReturns True if it finds a variable in the specified sequence, false otherwise.a in bnot inreturns True if it does not finds a variable in the specified sequence and false otherwise.a not in b

Example of Python Membership Operators

a = 10
b = 20
list = [1, 2, 3, 4, 5 ]

print ("a:", a, "b:", b, "list:", list)

if ( a in list ):
   print ("a is present in the given list")
else:
   print ("a is not present in the given list")

if ( b not in list ):
   print ("b is not present in the given list")
else:
   print ("b is present in the given list")

c=b/a
print ("c:", c, "list:", list)
if ( c in list ):
   print ("c is available in the given list")
else:
    print ("c is not available in the given list")

Output

a: 10 b: 20 list: [1, 2, 3, 4, 5]
a is not present in the given list
b is not present in the given list
c: 2.0 list: [1, 2, 3, 4, 5]
c is available in the given list

Python Identity Operators

Python identity operatorscompare the memory locations of two objects.

There are two Identity operators explained below −

OperatorDescriptionExampleisReturns True if both variables are the same object and false otherwise.a is bis notReturns True if both variables are not the same object and false otherwise.a is not b

Example of Python Identity Operators

a = [1, 2, 3, 4, 5]
b = [1, 2, 3, 4, 5]
c = a

print(a is c)
print(a is b)

print(a is not c)
print(a is not b)

Output

True
False
False
True

Python Operators Precedence

Operators precedence decides the order of the evaluation in which an operator is evaluated. Python operators have different levels of precedence. The following table contains the list of operators having highest to lowest precedence −

The following table lists all operators from highestprecedenceto lowest.

Read more about the Python operators precedence here:Python operators precedence