Python - Operators
Python Operators
Python operators are special symbols used to perform specific operations on one or more operands. The variables, 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 to Python 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 operators are 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 of a and b are 10 and 20, respectively) −
Operator | Name | Example |
---|---|---|
+ | Addition | a + b = 30 |
- | Subtraction | a – b = -10 |
* | Multiplication | a * b = 200 |
/ | Division | b / a = 2 |
% | Modulus | b % a = 0 |
** | Exponent | ab =1020 |
// | Floor Division | 9//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 operators compare 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 of a and b are 10 and 20, respectively) −
Operator | Name | Example |
---|---|---|
== | Equal | (a == b) is not true. |
!= | Not equal | (a != b) is true. |
> | Greater than | (a > b) is not true. |
< | Less than | (a < b) is true. |
>= | Greater than or equal to | (a >= b) is not true. |
<= | Less than or equal to | (a <= b) is true. |
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 operators are 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 −
Operator | Example | Same As |
---|---|---|
= | a = 10 | a = 10 |
+= | a += 30 | a = a + 30 |
-= | a -= 15 | a = a - 15 |
*= | a *= 10 | a = a * 10 |
/= | a /= 5 | a = a / 5 |
%= | a %= 5 | a = a % 5 |
**= | a **= 4 | a = a ** 4 |
//= | a //= 5 | a = a // 5 |
&= | a &= 5 | a = a & 5 |
|= | a |= 5 | a = a | 5 |
^= | a ^= 5 | a = a ^ 5 |
>>= | a >>= 5 | a = a >> 5 |
<<= | a <<= 5 | a = a << 5 |
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 operator works 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 −
Operator | Name | Example |
---|---|---|
& | AND | a & b |
| | OR | a | b |
^ | XOR | a ^ b |
~ | NOT | ~a |
<< | Zero fill left shift | a << 3 |
>> | Signed right shift | a >> 3 |
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 operators are 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 −
Operator | Name | Example |
---|---|---|
and | AND | a and b |
or | OR | a or b |
not | NOT | not(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’s membership operators test for membership in a sequence, such as strings, lists, or tuples.
There are two membership operators as explained below −
Operator | Description | Example |
---|---|---|
in | Returns True if it finds a variable in the specified sequence, false otherwise. | a in b |
not in | returns 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 operators compare the memory locations of two objects.
There are two Identity operators explained below −
Operator | Description | Example |
---|---|---|
is | Returns True if both variables are the same object and false otherwise. | a is b |
is not | Returns 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 highest precedence to lowest.
Sr.No. | Operator & Description |
---|---|
1 | **Exponentiation (raise to the power) |
2 | **~ + -**Complement, unary plus and minus (method names for the last two are +@ and -@) |
3 | *** / % //**Multiply, divide, modulo and floor division |
4 | **+ -**Addition and subtraction |
5 | **>> <<**Right and left bitwise shift |
6 | **&**Bitwise ‘AND’ |
7 | **^ |**Bitwise exclusive OR' and regular OR’ |
8 | **<= < > >=**Comparison operators |
9 | **<> == !=**Equality operators |
10 | **= %= /= //= -= += *= **=**Assignment operators |
11 | is is notIdentity operators |
12 | in not inMembership operators |
13 | not or andLogical operators |