hexadecimal_to_decimal.py

hex_table= {hex(i)[2:]: iforiinrange(16)} # Use [:2] to strip off the leading '0x'


defhex_to_decimal(hex_string: str) ->int:
"""
 Convert a hexadecimal value to its decimal equivalent
 #https://www.programiz.com/python-programming/methods/built-in/hex

 >>> hex_to_decimal("a")
 10
 >>> hex_to_decimal("12f")
 303
 >>> hex_to_decimal(" 12f ")
 303
 >>> hex_to_decimal("FfFf")
 65535
 >>> hex_to_decimal("-Ff")
 -255
 >>> hex_to_decimal("F-f")
 Traceback (most recent call last):
 ...
 ValueError: Non-hexadecimal value was passed to the function
 >>> hex_to_decimal("")
 Traceback (most recent call last):
 ...
 ValueError: Empty string was passed to the function
 >>> hex_to_decimal("12m")
 Traceback (most recent call last):
 ...
 ValueError: Non-hexadecimal value was passed to the function
 """
hex_string=hex_string.strip().lower()
ifnothex_string:
raiseValueError("Empty string was passed to the function")
is_negative=hex_string[0] =="-"
ifis_negative:
hex_string=hex_string[1:]
ifnotall(charinhex_tableforcharinhex_string):
raiseValueError("Non-hexadecimal value was passed to the function")
decimal_number=0
forcharinhex_string:
decimal_number=16*decimal_number+hex_table[char]
return-decimal_numberifis_negativeelsedecimal_number


if__name__=="__main__":
fromdoctestimporttestmod

testmod()