anchor.diff:  
   handle_info(next_event, #state{wait=Wait}) ->
       Ran = random:uniform(),         % 0..1
  -    X = round(50*Ran),              % bad code causing 1/0
  +    X = round(50*Ran)+1,              % bad code causing 1/0
       {_,Sec,_} = os:timestamp(),     % {MegaSec,Sec,MicroSec} since epoch
  -    FX = X * (Sec rem 100 + 1),     % rampy sample distribution
  +    Y = X * (Sec rem 100 + 1),     % rampy sample distribution
       OneOverX = 5000.0/X,            % spiky sample distribution
  -    imem_test_writer:write_test_record(X,FX,OneOverX,integer_to_list(fac(X))),
  +    imem_test_writer:write_test_record(X,Y,OneOverX,integer_to_list(fac(X))),
       erlang:send_after(Wait, self(), next_event),
       {noreply, #state{wait=Wait}}.
   
  
positive.code: wait(Wait) when is_integer(Wait) ->
      gen_server:call(?MODULE, {wait, Wait}). 
  
  write_test_record(X,FX,OneOverX,Comment) ->
      Record = #ddTest{ time=os:timestamp()
                      , x=X
                      , fX=FX
                      , oneOverX=OneOverX
                      , comment=Comment
                      },
      imem_meta:write(?ddTestName, Record).
  
  
negative.code: -record(ddTest,   % test table record definition with erlang types
                    { time      ::ddTimestamp()
                    , x         ::integer()
                    , y         ::integer()
                    , oneOverX  ::float()
                    , label     ::list()
                    }
         ).
  -define(ddTest, [timestamp,integer,integer,float,string]).  % test table DDerl types
  