Python/bit_manipulation/single_bit_manipulation_operations.py

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#!/usr/bin/env python3
"""Provide the functionality to manipulate a single bit."""
def set_bit(number: int, position: int) -> int:
"""
Set the bit at position to 1.
Details: perform bitwise or for given number and X.
Where X is a number with all the bits - zeroes and bit on given
position - one.
>>> set_bit(0b1101, 1) # 0b1111
15
>>> set_bit(0b0, 5) # 0b100000
32
>>> set_bit(0b1111, 1) # 0b1111
15
"""
return number | (1 << position)
def clear_bit(number: int, position: int) -> int:
"""
Set the bit at position to 0.
Details: perform bitwise and for given number and X.
Where X is a number with all the bits - ones and bit on given
position - zero.
>>> clear_bit(0b10010, 1) # 0b10000
16
>>> clear_bit(0b0, 5) # 0b0
0
"""
return number & ~(1 << position)
def flip_bit(number: int, position: int) -> int:
"""
Flip the bit at position.
Details: perform bitwise xor for given number and X.
Where X is a number with all the bits - zeroes and bit on given
position - one.
>>> flip_bit(0b101, 1) # 0b111
7
>>> flip_bit(0b101, 0) # 0b100
4
"""
return number ^ (1 << position)
def is_bit_set(number: int, position: int) -> bool:
"""
Is the bit at position set?
Details: Shift the bit at position to be the first (smallest) bit.
Then check if the first bit is set by anding the shifted number with 1.
>>> is_bit_set(0b1010, 0)
False
>>> is_bit_set(0b1010, 1)
True
>>> is_bit_set(0b1010, 2)
False
>>> is_bit_set(0b1010, 3)
True
>>> is_bit_set(0b0, 17)
False
"""
return ((number >> position) & 1) == 1
def get_bit(number: int, position: int) -> int:
"""
Get the bit at the given position
Details: perform bitwise and for the given number and X,
Where X is a number with all the bits - zeroes and bit on given position - one.
If the result is not equal to 0, then the bit on the given position is 1, else 0.
>>> get_bit(0b1010, 0)
0
>>> get_bit(0b1010, 1)
1
>>> get_bit(0b1010, 2)
0
>>> get_bit(0b1010, 3)
1
"""
return int((number & (1 << position)) != 0)
if __name__ == "__main__":
import doctest
doctest.testmod()