Operator precedence

           When an expression contains more than one operator, the order of evaluation depends on the order of operations.

        

  The acronym PEMDAS (Parentheses, Exponentiation, Multiplication, Division, Addition, Subtraction) is a useful way to remember the rules:

            * Parentheses have the highest precedence and can be used to force an expression to evaluate in the order you want. Since expressions in parentheses are evaluated first, 2 * (3-1)is 4, and (1+1)**(5-2) is 8.You can also use parentheses to make an expression easier to read, as in (minute* 100) / 60, even if it doesn’t change the result.

            * Exponentiation has the next highest precedence, so 1 + 2**3 is 9, not 27, and 2 *3**2 is 18, not 36.
            * Multiplication and Division have higher precedence than Addition and Subtraction. So 2*3-1 is 5, not 4, and 6+4/2 is 8, not 5.
            *Operators with the same precedence are evaluated from left to right (except exponentiation).

Boolean values

                                           Boolean data type have two values. They are 0 and 1. 0 represents False, 1 represents True. True and False are keyword . Boolean expressions is an expression that is either true or false. It use the operator == to compare two operands which produces true if the both operands are equal ,false  otherwise.

Program:

>>> 3==5

 False

>>> 6==6 

True

>>> True+True

2

>>> False+True

1

>>> False*True

0

Identity Operators

            They are used to check if two values (or variables) are located on the same part of the memory.

                         

Example:

x = 5 

y = 5 

print(x is not y)

print(x is y)

Output:

false

true

Membership Operators

                            Evaluates to find a value or a variable is in the specified sequence of string, list, tuple, dictionary or not.To check particular item in list or not, in and not in operators are used.

 

                         

Example :

x=[5,3,6,4,1]

>>> 5 in x True

>>> 5 not in x False

Bitwise operators

               A bitwise operation operates on one or more bit patterns at the level of individual bits.

                    

Example :

a = 60 # 60 = 0011 1100

b = 13 # 13 = 0000 1101

c = 0

c = a & b; # 12 = 0000 1100

print ("Line 1 - Value of c is ", c)

c = a | b; # 61 = 0011 1101

print ("Line 2 - Value of c is ", c) 

c = a ^ b;  # 49 = 0011 0001

print ("Line 3 - Value of c is ", c)

c = ~a; # -61 = 1100 0011

print ("Line 4 - Value of c is ", c)

c = a << 2; # 240 = 1111 0000

print ("Line 5 - Value of c is ", c)

c = a >> 2; # 15 = 0000 1111

print ("Line 6 - Value of c is ", c)

Output:

Line 1 - Value of c is 12

Line 2 - Value of c is 61

Line 3 - Value of c is 49

Line 4- Value of c is -61

Line 5 - Value of c is 240

Line 6 - Value of c is 15

Logical Operators

           Logical operators are the and, or, not operators.

             

 Example :   

a = True
b = False
print('a and b is',a and b)
print('a or b is',a or b)
print('not a is',not a)

Output:

x and y is false

x or y is true

not x is false

Assignment Operators

                  Assignment operators are used in Python to assign values to variables.

                       

Example :

a = 21

b = 10

c = a + b

print("Line 1 - Value of c is ", c)c += a

print("Line 2 - Value of c is ", c)c *= a

print("Line 3 - Value of c is ", c)c /= a

print("Line 4 - Value of c is ", c)c = 2 c %= a

print("Line 5 - Value of c is ", c) c **= a

print("Line 6 - Value of c is ", c) c //= a

print("Line 7 - Value of c is ", c)

output:

Line 1 - Value of c is 31

Line 2 - Value of c is 52

Line 3 - Value of c is 1092

Line 4 - Value of c is 52.0

Line 5 - Value of c is 2

Line 6 - Value of c is 2097152 

Line 7 - Value of c is 99864