# What is an operator?

Simple answer can be given using expression *4 + 5 is equal to 9*. Here 4 and 5 are called operands and + is called operator. Python language supports following type of operators.

- Arithmetic Operators
- Comparision Operators
- Logical (or Relational) Operators
- Assignment Operators
- Conditional (or ternary) Operators

Lets have a look on all operators one by one.

# Python Arithmetic Operators:

Assume variable a holds 10 and variable b holds 20 then:

Operator | Description | Example |
---|---|---|

+ | Addition – Adds values on either side of the operator | a + b will give 30 |

– | Subtraction – Subtracts right hand operand from left hand operand | a – b will give -10 |

* | Multiplication – Multiplies values on either side of the operator | a * b will give 200 |

/ | Division – Divides left hand operand by right hand operand | b / a will give 2 |

% | Modulus – Divides left hand operand by right hand operand and returns remainder | b % a will give 0 |

** | Exponent – Performs exponential (power) calculation on operators | a**b will give 10 to the power 20 |

// | Floor Division – The division of operands where the result is the quotient in which the digits after the decimal point are removed. | 9//2 is equal to 4 and 9.0//2.0 is equal to 4.0 |

# Python Comparison Operators:

Assume variable a holds 10 and variable b holds 20 then:

Operator | Description | Example |
---|---|---|

== | Checks if the value of two operands are equal or not, if yes then condition becomes true. | (a == b) is not true. |

!= | Checks if the value of two operands are equal or not, if values are not equal then condition becomes true. | (a != b) is true. |

<> | Checks if the value of two operands are equal or not, if values are not equal then condition becomes true. | (a <> b) is true. This is similar to != operator. |

> | Checks if the value of left operand is greater than the value of right operand, if yes then condition becomes true. | (a > b) is not true. |

< | Checks if the value of left operand is less than the value of right operand, if yes then condition becomes true. | (a < b) is true. |

>= | Checks if the value of left operand is greater than or equal to the value of right operand, if yes then condition becomes true. | (a >= b) is not true. |

<= | Checks if the value of left operand is less than or equal to the value of right operand, if yes then condition becomes true. | (a <= b) is true. |

# Python Assignment Operators:

Assume variable a holds 10 and variable b holds 20 then:

Operator | Description | Example |
---|---|---|

= | Simple assignment operator, Assigns values from right side operands to left side operand | c = a + b will assigne value of a + b into c |

+= | Add AND assignment operator, It adds right operand to the left operand and assign the result to left operand | c += a is equivalent to c = c + a |

-= | Subtract AND assignment operator, It subtracts right operand from the left operand and assign the result to left operand | c -= a is equivalent to c = c – a |

*= | Multiply AND assignment operator, It multiplies right operand with the left operand and assign the result to left operand | c *= a is equivalent to c = c * a |

/= | Divide AND assignment operator, It divides left operand with the right operand and assign the result to left operand | c /= a is equivalent to c = c / a |

%= | Modulus AND assignment operator, It takes modulus using two operands and assign the result to left operand | c %= a is equivalent to c = c % a |

**= | Exponent AND assignment operator, Performs exponential (power) calculation on operators and assign value to the left operand | c **= a is equivalent to c = c ** a |

//= | Floor Dividion and assigns a value, Performs floor division on operators and assign value to the left operand | c //= a is equivalent to c = c // a |

# Python Bitwise Operators:

Bitwise operator works on bits and perform 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

Operator | Description | Example |
---|---|---|

& | Binary AND Operator copies a bit to the result if it exists in both operands. | (a & b) will give 12 which is 0000 1100 |

| | Binary OR Operator copies a bit if it exists in eather operand. | (a | b) will give 61 which is 0011 1101 |

^ | Binary XOR Operator copies the bit if it is set in one operand but not both. | (a ^ b) will give 49 which is 0011 0001 |

~ | Binary Ones Complement Operator is unary and has the efect of ‘flipping’ bits. | (~a ) will give -60 which is 1100 0011 |

<< | Binary Left Shift Operator. The left operands value is moved left by the number of bits specified by the right operand. | a << 2 will give 240 which is 1111 0000 |

>> | Binary Right Shift Operator. The left operands value is moved right by the number of bits specified by the right operand. | a >> 2 will give 15 which is 0000 1111 |

# Python Logical Operators:

There are following logical operators supported by Python language

Assume variable a holds 10 and variable b holds 20 then:

Operator | Description | Example |
---|---|---|

and | Called Logical AND operator. If both the operands are true then then condition becomes true. | (a and b) is true. |

or | Called Logical OR Operator. If any of the two operands are non zero then then condition becomes true. | (a or b) is true. |

not | Called Logical NOT Operator. Use to reverses the logical state of its operand. If a condition is true then Logical NOT operator will make false. | not(a and b) is false. |

# Python Membership Operators:

In addition to the operators discussed previously, Python has membership operators, which test for membership in a sequence, such as strings, lists, or tuples.

There are two membership operators explained below:

Operator | Description | Example |
---|---|---|

in | Evaluates 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 in | Evaluates 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 a member of sequence y. |

# Python Identity Operators:

Identity operators compare the memory locations of two objects.

There are two Identity operators explained below:

Operator | Description | Example |
---|---|---|

is | Evaluates 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 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). |

# Python Operators Precedence

The following table lists all operators from highest precedence to lowest.

Operator | Description |
---|---|

** | Exponentiation (raise to the power) |

~ + – | Ccomplement, unary plus and minus (method names for the last two are +@ and -@) |

* / % // | Multiply, divide, modulo and floor division |

+ – | Addition and subtraction |

>> << | Right and left bitwise shift |

& | Bitwise ‘AND’ |

^ | | Bitwise exclusive `OR’ and regular `OR’ |

<= < > >= | Comparison operators |

<> == != | Equality operators |

= %= /= //= -= += *= **= | Assignment operators |

is is not | Identity operators |

in not in | Membership operators |

not or and | Logical operators |