Python Technology Tutorial

Python: Operators

Can we add ? Can we subtract ? Can we perform operations in python ? Well, read on to know more!

The heart, the soul, and the foundation of any programming language, are it’s operators. They help build the logic, and transform your ideas into functioning models. They can manipulate values, functions, and help achieve our targets when used effectively.

Types of Operators

Python language supports the following types of operators.

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

Now, we shall look at each arithmetic operator with examples, so that it will be a lot easier for one to understand, how does Python, and their operators, really work!

Python Arithmetic Operators

Let’s assume we have two variable, a =5 and b = 10. Thus:

OperatorDescriptionExample
+ AdditionAdds values on either side of the operator.a + b = 15
– SubtractionSubtracts right hand operand from left hand operand.a – b = -5
* MultiplicationMultiplies values on either side of the operatora * b = 50
/ DivisionDivides left hand operand by right hand operandb / a = 2
% ModulusDivides left hand operand by right hand operand and returns remainderb % a = 0
** ExponentPerforms exponential (power) calculation on operatorsa**b =
5 to the power 10
//Floor Division – The division of operands where the result is the quotient in which the digits after the decimal point are removed. But if one of the operands is negative, the result is floored, i.e., rounded away from zero (towards negative infinity) −9//2 = 4 and 9.0//2.0 = 4.0, -11//3 = -4, -11.0//3 = -4.0

Python Comparison Operators

These operators compare the values on either sides of them and decide the relation among them. They are also called Relational operators.

Let’s assume we have two variable, a =5 and b = 10. Thus:

OperatorDescriptionExample
==If the values of two operands are equal, then the condition becomes true.(a == b) is not true.
!=If values of two operands are not equal, then condition becomes true.(a != b) is true.
<>If values of two operands are not equal, then condition becomes true.(a <> b) is true. This is similar to != operator.
>If the value of left operand is greater than the value of right operand, then condition becomes true.(a > b) is not true.
<If the value of left operand is less than the value of right operand, then condition becomes true.(a < b) is true.
>=If the value of left operand is greater than or equal to the value of right operand, then condition becomes true.(a >= b) is not true.
<=If the value of left operand is less than or equal to the value of right operand, then condition becomes true.(a <= b) is true.

Python Assignment Operators

Let’s assume we have two variable, a =5 and b = 10. Thus:

OperatorDescriptionExample
=Assigns values from right side operands to left side operandc = a + b assigns value of a + b into c
+= Add ANDIt adds right operand to the left operand and assign the result to left operandc += a is equivalent to c = c + a
-= Subtract ANDIt subtracts right operand from the left operand and assign the result to left operandc -= a is equivalent to c = c – a
*= Multiply ANDIt multiplies right operand with the left operand and assign the result to left operandc *= a is equivalent to c = c * a
/= Divide ANDIt divides left operand with the right operand and assign the result to left operandc /= a is equivalent to c = c / ac /= a is equivalent to c = c / a
%= Modulus ANDIt takes modulus using two operands and assign the result to left operandc %= a is equivalent to c = c % a
**= Exponent ANDPerforms exponential (power) calculation on operators and assign value to the left operandc **= a is equivalent to c = c ** a
//= Floor DivisionIt performs floor division on operators and assign value to the left operandc //= a is equivalent to c = c // a

Python Bitwise Operators

Bitwise operator works on bits and performs bit by bit operation. Assume if a = 60; and b = 13; Now in binary format they will be as follows −

a = 0011 1100

b = 0000 1101

—————–

a&b = 0000 1100

a|b = 0011 1101

a^b = 0011 0001

~a  = 1100 0011

There are following Bitwise operators supported by Python language

OperatorDescriptionExample
& Binary ANDOperator copies a bit to the result if it exists in both operands(a & b) (means 0000 1100)
| Binary ORIt copies a bit if it exists in either operand.(a | b) = 61 (means 0011 1101)
^ Binary XORIt copies the bit if it is set in one operand but not both.(a ^ b) = 49 (means 0011 0001)
~ Binary Ones ComplementIt is unary and has the effect of ‘flipping’ bits.(~a ) = -61 (means 1100 0011 in 2’s complement form due to a signed binary number.
<< Binary Left ShiftThe left operands value is moved left by the number of bits specified by the right operand.a << 2 = 240 (means 1111 0000)
>> Binary Right ShiftThe left operands value is moved right by the number of bits specified by the right operand.a >> 2 = 15 (means 0000 1111)

Python Logical Operators

There are following logical operators supported by Python language. Let’s assume we have two variable, a =5 and b = 10. Thus:

OperatorDescriptionExample
and Logical ANDIf both the operands are true then condition becomes true.(a and b) is true.
or Logical ORIf any of the two operands are non-zero then condition becomes true.(a or b) is true.
not Logical NOTUsed to reverse the logical state of its operand.Not(a and b) is 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:

OperatorDescriptionExample
inEvaluates to true if it finds a variable in the specified sequence and false otherwise.x in y, here in results in a 1 if x is a member of sequence y.
not inEvaluates to true if it does not finds a variable in the specified sequence and false otherwise.x not in y, here not in results in a 1 if x is not a member of sequence y.

Python Identity Operators

Identity operators compare the memory locations of two objects. There are two Identity operators explained below −

OperatorDescriptionExample
isEvaluates to true if the variables on either side of the operator point to the same object and false otherwise.x is y, here is results in 1 if id(x) equals id(y).
is notEvaluates to false if the variables on either side of the operator point to the same object and true otherwise.x is not y, here is not results in 1 if id(x) is not equal to id(y).

Python Operators 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
11is is not Identity operators
12in not in Membership operators
13not or and Logical operators

In case, you have any questions, feel free to mention your questions as comments to this specific post. I will try and answer at the earliest.

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