Converting Decimal to Hexadecimal in python

Question

1. i am getting answer as 7D while i should be getting 7D0. I actually dont know how to solve it:
2. my test case at the beginning was 31 which answer was correct 1F but as i go towards higher number my code doesnt work.
3. using loops might be more efficient but i am not too comfortable with loop right now

4. please help !!!

    def dec2hex(n): x1 =0 counter = 0 answer = "" if n<=0: answer =answer + "0" else: while (n >16): counter +=1 n = n /16 x = n if(x <16 ): x = int(n) break else: continue if ((nx) *16 <16 ): counter1 = 1 else: counter1 = counter -1 rem = (nx) * (16**(counter1)) if rem >16: while (n >16): rem = rem /16 x1 = rem if(x1 <16 ): x1 = int(rem) break else: continue if n < 10: answer =answer + str(int(x)) if (rem ==10 or x1 ==10): answer = answer + "A" if (rem ==11 or x1 ==11): answer = answer + "B" if (rem ==12 or x1 ==12): answer = answer + "C" if (rem ==13 or x1 ==13): answer = answer + "D" if (rem ==14 or x1 ==14): answer = answer + "E" if (rem ==15 or x1 ==15): answer = answer + "F" print(counter,rem,x1,n,counter,x) return answer 

   dec2hex(2000)

Answer 1

I would like to propose this approach to the problem. A while loop is used to cycle the main division and the reminder calculus A for loop is used to invert the final answer string

The while loop condition exclude the case in which 0 is entered becasue the division remainder will be always zero and the loop will be infinite. In this case the answer will be forced to 0 by the first if.

def dec2hex(hexnum):
hexstring = ["0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "A", "B", "C", "D", "E", "F"]
counter = 0
remainder = []
answer = ""
if hexnum > 0:
    while hexnum > 0:
        remainder.append(hexnum % 16)
        hexnum = hexnum // 16
        counter = counter + 1
    for reverse in remainder[::-1]:
        answer = answer + hexstring[reverse]
else:
    answer = "0"
return answer

print(dec2hex(2000))

Answer 2

The most elegant answer I can think of is to format a string literal and it will convert the value for you

3.6+ (f-strings)

>>> d = 2000
>>> print(f'{d:X}')
7D0

pre-3.6 (string format function)

>>> d = 2000
>>> print('{:X}'.format(d))
7D0

https://docs.python.org/3/reference/lexical_analysis.html#f-strings

https://docs.python.org/3/library/string.html#formatspec