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Chubek/bitwise_word.py

Created March 3, 2023 12:25
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Bitwise operations in Python on words...
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bitwise_word.py
def f_dec_to_word(dec: int) -> list[str]:
bits = [cBIT_ZERO] * 16
i = 15
while dec > 0:
bits[i] = str(int(dec % 2))
dec //= 2
i -= 1
return bits
def f_force_uint16_overflow(dec: int) -> int:
bits = f_dec_to_word(dec)
if all([b == cBIT_ONE for b in bits]):
return 0
return dec
def f_and_bit(a: str, b: str) -> str:
if all([binn == cBIT_ONE for binn in [a, b]]):
return cBIT_ONE
else:
return cBIT_ZERO
def f_or_bit(a: str, b: str) -> str:
if all([binn == cBIT_ZERO for binn in [a, b]]):
return cBIT_ZERO
return cBIT_ONE
def f_xor_bit(a: str, b: str) -> str:
if all([binn == cBIT_ONE
for binn in [a, b]]) or all([binn == cBIT_ZERO
for binn in [a, b]]):
return cBIT_ZERO
return cBIT_ONE
def f_not_bit(b: str) -> str:
return cBIT_ONE if b == cBIT_ZERO else cBIT_ZERO
def f_rotate_left_word(num: int, by=cMOD_ITER) -> int:
bits = f_dec_to_word(num)
left_most_bits = bits[:by]
right_most_bits = bits[by:]
rotated_bits = right_most_bits + left_most_bits
return int("".join(rotated_bits), 2)
def f_rotate_right_word(num: int, by=cMOD_ITER) -> int:
bits = f_dec_to_word(num)
left_most_bits = bits[8 - by:]
right_most_bits = bits[:by]
rotated_bits = right_most_bits + left_most_bits
return int("".join(rotated_bits), 2)
def f_shift_left_word(num: int, by: int) -> int:
bits = f_dec_to_word(num)
num_zeros = [cBIT_ZERO] * by
cut = bits[by:]
shift_left = cut + num_zeros
return int("".join(shift_left), 2)
def f_shift_right_word(num: int, by: int) -> int:
bits = f_dec_to_word(num)
num_zeros = [cBIT_ZERO] * by
cut = bits[:len(bits) - by]
shift_right = num_zeros + cut
return int("".join(shift_right), 2)
def f_and_word(a: int, b: int) -> int:
bits_a = f_dec_to_word(a)
bits_b = f_dec_to_word(b)
anded = [f_and_bit(aa, bb) for aa, bb in zip(bits_a, bits_b)]
return int("".join(anded), 2)
def f_or_word(a: int, b: int) -> int:
bits_a = f_dec_to_word(a)
bits_b = f_dec_to_word(b)
ored = [f_or_bit(aa, bb) for aa, bb in zip(bits_a, bits_b)]
return int("".join(ored), 2)
def f_xor_word(a: int, b: int) -> int:
bits_a = f_dec_to_word(a)
bits_b = f_dec_to_word(b)
xored = [f_xor_bit(aa, bb) for aa, bb in zip(bits_a, bits_b)]
return int("".join(xored), 2)
def f_not_word(b: int) -> int:
bits_b = f_dec_to_word(b)
notted = [f_not_bit(bb) for bb in bits_b]
return int("".join(notted), 2)
def f_reverse_complement_word(b: int) -> int:
bits_b = f_dec_to_word(b)
bits_b[0] = f_not_bit(bits_b[0])
return int("".join(bits_b), 2)
def f_bitwise_add_words(a: int, b: int) -> int:
while b != 0:
carry = f_and_word(a, b)
a = f_force_uint16_overflow(f_xor_word(a, b))
b = f_shift_left_word(carry, 1)
return a
def f_bitwise_sub_words(a: int, b: int) -> int:
b = f_bitwise_add_words(f_not_word(b), 1)
while b != 0:
carry = f_shift_left_word(f_and_word(a, b), 1)
a = f_force_uint16_overflow(f_xor_word(a, b))
b = carry
return a
def f_bitwise_divmod_words(n: int, d: int) -> tuple[int, int]:
q = 0
r = n
while r >= d:
q = f_bitwise_add_words(q, 1)
r = f_bitwise_sub_words(r, d)
return q, r
def f_bitwise_div_words(n: int, d: int) -> int:
return f_bitwise_divmod_words(n, d)[0]
def f_bitwise_mod_words(n: int, d: int) -> int:
return f_bitwise_divmod_words(n, d)[1]
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