rem -----------------------------------------------------------------------
rem Filename:   dbms_numsystem.sql
rem Purpose:    Package with functions to convert numbers between the 
rem             Decimal, Binary, Octal and Hexidecimal numbering systems.
rem Usage:      See sampels at the bottom of this file
rem Author:     Frank Naude, 17 February 2003
rem -----------------------------------------------------------------------

set serveroutput on

CREATE OR REPLACE PACKAGE dbms_numsystem AS
   function bin2dec (binval in char  ) RETURN number;
   --function dec2bin (N      in char) RETURN varchar2; 
   --function dec2binn (N      in number) RETURN varchar2; 
END dbms_numsystem;
/
show errors

CREATE OR REPLACE PACKAGE BODY dbms_numsystem AS

FUNCTION bin2dec (binval in char) RETURN number IS
  i                 number;
  digits            number;
  result            number := 0;
  current_digit     char(1);
  current_digit_dec number;
BEGIN
  digits := length(binval);
  for i in 1..digits loop
     current_digit := SUBSTR(binval, i, 1);
     current_digit_dec := to_number(current_digit);
     result := (result * 2) + current_digit_dec;
  end loop;
  return result;
END bin2dec;

/*

insert other package functions here:

FUNCTION dec2bin (decval in char) RETURN varchar2 IS
  binval varchar2(64);
...

end dec2bin;

FUNCTION dec2binn (N in number) RETURN varchar2 IS
  binval varchar2(64);
  N2     number := N;
...

end dec2binn;

*/

END dbms_numsystem;
/
show errors

-- Examples:
select dbms_numsystem.bin2dec('00000101') from dual;
select dbms_numsystem.bin2dec('11111111') from dual;
--select dbms_numsystem.dec2bin(22)      from dual;
--select dbms_numsystem.dec2binn(22)      from dual;