Operators are the constructs, which can manipulate the value of operands. Consider the expression 4 + 5 = 9. Here, 4 and 5 are called the operands and + is called the operator.
Python language supports the following types of operators −
- Arithmetic Operators
- Comparison (Relational) Operators
- Assignment Operators
- Logical Operators
- Bitwise Operators
- Membership Operators
- Identity Operators
Assume variable a holds the value 10 and variable b holds the value 21, then -
- Addition ( + ): a + b = 31
- Subtraction ( - ):a – b = -11
- Multiplication ( * ): a * b = 210
- Division ( / ): b / a = 2.1
- Modulus ( % ): b % a = 1
- Exponent ( ** ): a**b =10 to the power 20
These operators compare the values on either side of them and decide the relation among them. They are also called Relational operators.
Assume variable a holds the value 10 and variable b holds the value 20.
- ( == ): If the values of two operands are equal, then the condition becomes true.
Ex: (a == b) is not true. - ( != ): If values of two operands are not equal, then condition becomes true.
Ex: (a != b) is true. - ( > ): If the value of left operand is greater than the value of right operand, then condition becomes true.
Ex: (a > b) is not true. - ( < ): If the value of left operand is less than the value of right operand, then condition becomes true.
Ex: (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.
Ex: (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.
Ex: (a <= b) is true.
Assume variable a holds the value 10 and variable b holds the value 20.
- ( = ): Assigns values from right side operands to left side operand
Ex: c = a + b assigns value of a + b into c - ( += ): It adds right operand to the left operand and assign the result to left operand
Ex: c += a is equivalent to c = c + a - ( -= ): It subtracts right operand from the left operand and assign the result to left operand
Ex: c -= a is equivalent to c = c - a
The following logical operators are supported by Python language. Assume variable a holds True and variable b holds False.
- and Logical AND: If both the operands are true then condition becomes true.
Ex: (a and b) is False. - or Logical OR: If any of the two operands are non-zero then condition becomes true.
Ex: (a or b) is True. - not Logical NOT: Used to reverse the logical state of its operand.
Ex: Not(a and b) is True.
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 then, a&b = 0000 1100 a|b = 0011 1101 a^b = 0011 0001 ~a = 1100 0011
Python’s membership operators test for membership in a sequence, such as strings, lists, or tuples. There are two membership operators as explained below −
- in: Evaluates to true if it finds a variable in the specified sequence and false otherwise.
Ex: x in y, here in results in a 1 if x is a member of sequence y. - not in: Evaluates to true if it does not finds a variable in the specified sequence and false otherwise.
Ex: x not in y, here not in results in a 1 if x is not a member of sequence y.
Identity operators compare the memory locations of two objects. There are two Identity operators as explained below −
- is: Evaluates to true if the variables on either side of the operator point to the same object and false otherwise.
Ex: x is y, here is results in 1 if id(x) equals id(y). - is not: Evaluates 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).