The library supports at present bases up to base 36 (the digits 0...9 and the
letters A...Z). If you want more, you must edit the tables in the file
apfloat.cc:

// Numeric value to character, up to base 36
char chartable[] = {'0', '1', '2', '3', '4', '5', '6', '7', '8',
                    '9', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H',
                    'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q',
                    'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z'};

- This is the table of which symbol each numeric value represents. Like 0
  is printed out and read as '0', 1 as '1' etc.

// Character to numeric value, up to base 36
rawtype valuetable[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                        0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 0, 0, 0, 0, 0,
                        0, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24,
                        25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 0, 0, 0, 0, 0,
                        0, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24,
                        25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 0, 0, 0, 0, 0,
                        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};

- This is the table which numeric value a character corresponds to. Like the
  table index number 49 (the character '1') corresponds to the value 1.

- Note that the numbers are printed out and read (as the character string
  constructor) in the base used. The symbol used to define the exponential
  might confuse things. It's by default 'e' or 'E' (the standard
  floating-point input/output format). If you use base greater than 14, it
  will also correspond to a digit. So you probably want to change the
  symbols used for the exponent (in the file apfloat.cc):

// Characters used in exponent notation (do not mix with e.g. hex digits)
const char Expchar[2] = {'e', 'E'};

- Note that the exponent is always expressed in decimal, although it means
  *Basedigit^exp.
