Bitwise vs. logical Boolean expressions in Python: Key differences and practical applications

[Rajeev Bagra]

Source: Generated through AI tool

 In Python, bitwise and logical boolean expressions are two different ways to perform logical operations, and they serve different purposes. Let’s break down each one in detail:

Logical Boolean Expressions

Logical boolean expressions use the and, or, and not operators to evaluate conditions based on their truth values. These operators work with boolean values (True and False) and are typically used in conditional statements.

Operators:

• and: Returns True if both operands are true.
• or: Returns True if at least one operand is true.
• not: Returns the opposite of the operand’s boolean value.

Examples:

a = True
b = False

# Logical AND
result_and = a and b # False

# Logical OR
result_or = a or b # True

# Logical NOT
result_not = not a # False

Bitwise Boolean Expressions

Bitwise boolean expressions use the &, |, ^, ~, <<, and >> operators to perform operations on the binary representations of integers. These operators work at the bit level.

Operators:

• & (bitwise AND): Sets each bit to 1 if both bits are 1.
• | (bitwise OR): Sets each bit to 1 if one of the bits is 1.
• ^ (bitwise XOR): Sets each bit to 1 if only one of the bits is 1.
• ~ (bitwise NOT): Inverts all the bits.
• << (left shift): Shifts bits to the left by the specified number of positions. – >> (right shift): Shifts bits to the right by the specified number of positions.

Examples:

a = 0b1010 # 10 in binary
b = 0b1100 # 12 in binary

# Bitwise AND
result_and = a & b # 0b1000 (8 in decimal)

# Bitwise OR
result_or = a | b # 0b1110 (14 in decimal)

# Bitwise XOR
result_xor = a ^ b # 0b0110 (6 in decimal)

# Bitwise NOT
result_not = ~a # -11 in decimal (Two's complement representation)

# Left Shift
result_left_shift = a << 2 # 0b101000 (40 in decimal) # Right Shift result_right_shift = a >> 2 # 0b0010 (2 in decimal)

Key Differences

1. Data Types:

– Logical boolean expressions operate on boolean values (True and False).
– Bitwise boolean expressions operate on integers and their binary representations.

1. Usage:

– Logical boolean expressions are used for control flow and conditional logic.
– Bitwise boolean expressions are used for low-level operations, such as manipulating individual bits within an integer.

1. Operators:

– Logical boolean operators: and, or, not.
– Bitwise boolean operators: &, |, ^, ~, <<, >>.

1. Short-Circuiting:

– Logical boolean operators (and, or) short-circuit. This means they stop evaluating as soon as the result is determined. For example, in a and b, if a is False, b is not evaluated.
– Bitwise operators do not short-circuit; they always evaluate both operands.

Practical Example

Logical Boolean Expression:

x = 5
y = 10

if x < 10 and y > 5:
print("Both conditions are true")
# Output: Both conditions are true

Bitwise Boolean Expression:

x = 5 # 0b0101
y = 3 # 0b0011

result = x & y
print(bin(result)) # Output: 0b0001 (1 in decimal)

In summary, logical boolean expressions are used for high-level logical operations involving true/false values, while bitwise boolean expressions are used for low-level operations on the binary representations of integers. They serve different purposes and are suited for different types of problems.

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