I am trying to append some hex values in python and I always seem to get 0x between the number. From what I searched, either this is not possible without converting it into a lit of values ?? I am not sure.
a = 0x7b
b = 0x80000
hex(a) + hex(b) = 0x7b0x80000
I dont want the 0x in the middle - I need, 0x7b80000. is there any other way to do this? If I convert to integer I get the sum of the two and converting it to hex is a different value than 0x7b80000
I don't think you want to "append" them. Doing integer arithmetic by using strings is a bad idea. I think you want to bit-shift a into the right place and OR them together:
>>> a = 0x7B
>>> b = 0x80000
>>>
>>> hex( (a<<20) | b )
'0x7b80000'
Perhaps if you were more specific about what these numbers are and what exactly you're trying to accomplish I could provide a more general answer.
a=0x32, b=0x32. Assuming 20 == bit size of b
It's been 7 years but the accepted answer is wrong and this post still appears in the first place in google searches; so here is a correct answer:
import math
def append_hex(a, b):
sizeof_b = 0
# get size of b in bits
while((b >> sizeof_b) > 0):
sizeof_b += 1
# every position in hex in represented by 4 bits
sizeof_b_hex = math.ceil(sizeof_b/4) * 4
return (a << sizeof_b_hex) | b
The accepted answer doesn't make sense (you can check it with values a=10, b=1a). In this solution, we search for the nearest divider of 4 - since every hex value is represented by 4 bits - and then move the first value this time of bits.
0x00 ?0x00 (or 0x0, or 0x0000000000000) mean to you?0x00 is the exact same as 0 or 0x000000000000000. They're integers of an unspecified size. The fact that you show it with two zeros means nothing from the algorithm's standpoint. That's why, without explicitly stating the size of the integers involved, this entire question is arbitrary!You can use f-string formatting with Python 3:
>>> a = 0x7b
>>> b = 0x80000
>>> f'0x{a:x}{b:x}'
'0x7b80000'
This is a more generic way to append hex / int / bin values.
Only works for positive values of b.
a = 0x7b
b = 0x80000
def append_hex(a, b):
sizeof_b = 0
# get size of b in bits
while((b >> sizeof_b) > 0):
sizeof_b += 1
# align answer to nearest 4 bits (hex digit)
sizeof_b += sizeof_b % 4
return (a << sizeof_b) | b
print(hex(append_hex(a, b)))
Basically you have to find the highest set bit that b has.
Align that number to the highest multiple of 4 since that's what hex chars are.
Append the a to the front of the highest multiple of 4 that was found before.