Variables and Operators

In Python, variables are used to store data values. These data values can be manipulated using operators.

Variables

A variable is a name that refers to a value stored in memory. In Python, variables are created by assigning a value to a name. Here's an example:

            x = 42
        

In this example, the variable x is assigned the value 42. The equal sign (=) is used to assign a value to a variable.

Variable names can contain letters, numbers, and underscores, but they cannot start with a number. Variable names are case-sensitive, so x and X are two different variables.

Operators

Operators are used to perform operations on values stored in variables. Python supports several types of operators, including:

• Arithmetic operators
• Comparison operators
• Assignment operators
• Logical operators
• Identity operators
• Membership operators
• Bitwise operators

Arithmetic Operators

Arithmetic operators are used to perform mathematical operations on numbers. Python supports the following arithmetic operators:

• '+' (addition)
• '-' (subtraction)
• '*' (multiplication)
• '/' (division)
• '%' (modulus)
• '**' (exponentiation)
• '//' (floor division)

Here are some examples of arithmetic operations in Python:

            x = 10
            y = 3

            print(x + y)  # Output: 13
            print(x - y)  # Output: 7
            print(x * y)  # Output: 30
            print(x / y)  # Output: 3.3333333333333335
            print(x % y)  # Output: 1
            print(x ** y) # Output: 1000
            print(x // y) # Output: 3

        

Comparison Operators

Comparison operators are used to compare values. Python supports the following comparison operators:

• == (equal to)
• != (not equal to)
• < (less than)
• > (greater than)
• <= (less than or equal to)
• >= (greater than or equal to))

Here are some examples of comparison operators in Python:

            x = 10
            y = 3

            print(x == y)  # Output: False
            print(x != y)  # Output: True
            print(x < y)   # Output: False
            print(x > y)   # Output: True
            print(x <= y)  # Output: False
            print(x >= y)  # Output: True
        

Assignment Operators

Assignment operators are used to assign values to variables. Python supports several assignment operators, including:

• = (simple assignment)
• += (addition assignment)
• -= (subtraction assignment)
• *= (multiplication assignment)
• /= (division assignment)
• %= (modulus assignment)
• **= (exponentiation assignment)
• //= (floor division assignment)

Here are some examples of assignment operators in Python:

            x = 10

            x += 5
            print(x)  # Output: 15

            x -= 3
            print(x)  # Output: 12

            x *= 2
            print(x)  # Output: 24

            x /= 4
            print(x)  # Output: 6.0

            x %= 3
            print(x)  # Output: 0.0
        

Logical Operators

Logical operators are used to combine boolean expressions. Python supports three logical operators:

• and (logical AND)
• or (logical OR)
• not (logical NOT)

Here are some examples of logical operators in Python:

            x = True
            y = False

            print(x and y)  # Output: False
            print(x or y)   # Output: True
            print(not x)    # Output: False
        

Identity Operators

Identity operators are used to compare the memory locations of two objects. Python supports two identity operators:

• is (true if the operands are identical)
• is not (true if the operands are not identical)

Here are some examples of identity operators in Python:

            x = [1, 2, 3]
            y = [1, 2, 3]
            z = x

            print(x is y)      # Output: False
            print(x is not y)  # Output: True
            print(x is z)      # Output: True
        

Membership Operators

Membership operators are used to test whether a value is a member of a sequence. Python supports two membership operators:

• in (true if the value is found in the sequence)
• not in (true if the value is not found in the sequence)

Here are some examples of membership operators in Python:

            x = [1, 2, 3]

            print(2 in x)      # Output: True
            print(4 not in x)  # Output: True
        

Bitwise Operators

Bitwise operators are used to perform bitwise operations on integers. Python supports the following bitwise operators:

• & (bitwise AND)
• | (bitwise OR)
• ^ (bitwise XOR)
• ~ (bitwise NOT)
• << (left shift)
• >> (right shift)

Here are some examples of bitwise operators in Python:

            x = 10
            y = 5

            print(x & y)   # Output: 0
            print(x | y)   # Output: 15
            print(x ^ y)   # Output: 15
            print(~x)      # Output: -11
            print(x << 1)  # Output: 20
            print(y >> 1)  # Output: 2

        

Conclusion

We had just covered the basics of variables and operators in Python. We looked at how variables are created and used, and we covered the different types of operators available in Python, including arithmetic operators, comparison operators, assignment operators, logical operators, identity operators, membership operators, and bitwise operators. By mastering these fundamental concepts, you'll be well on your way to becoming proficient in Python programming.