multitronic_base_converter.py

#Converts a user-defined number from one user-defined base to another
#Highest base determined by number of possible number symbols as defined in LOOKUP

#Builds a dictionary using enumerate function on chosen order of chosen number symbols

LOOKUP = {b: i for i, b in enumerate('0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ')}
_LOOKUP = {b: i for i, b in LOOKUP.items()}
#Function = 2 part process, converts user number to denary (if not already) and then from denary to specified base
#Multipliers, factors and operands derived from user-specified base values 
def convert(inputnum, frombase, tobase):
    """
    >>> convert('0', 2, 10)
    '0'
    >>> convert('1100', 2, 10)
    '12'
    >>> convert('12', 10, 2)
    '1100'
    >>> convert('AA', 16, 10)
    '170'
    """
    decsum = 0
    #Cconverts any extra symbols back to decimal numerals and reverses the input number
    decval = (LOOKUP[i] for i in reversed(inputnum))
    
    #Converts user number to denary
    for i, j in enumerate(decval):
        decsum += j * (frombase**i)
    output = "" 
    #Converts (possibly new) denary number to specified base
    while decsum > 0:
        remainder = decsum % (tobase)
        output += str(_LOOKUP[remainder])
        decsum = int((decsum - remainder) / (tobase))
    if not output:
        output = '0'
    return output

if __name__ == '__main__':
    #Creates key variables from user input (base values converted to integers to be called later)
    inputnum = (input('Enter your number: '))
    frombase = int(input('In which base is your number?: '))
    tobase = int(input('To which base would you like to convert it?: '))
    #Prefaces output with user input and calls main function based on input
    print(f"Your base {frombase} number {inputnum} in base {tobase} = {convert(inputnum, frombase, tobase)}")