plpgsql question

  I am trying to calculate a value from a current record in a query and
can't seem to get it working.

Here is the shortened query;
SELECT
       s.id,
       r.the_date_time,
       s.open_price,
       s.high_price,
       s.low_price,
       s.close_price,
       thesheet_onepair.symbol,
       r.buy_long,
       r.buy_stop,
       r.sell_cl,
       r.stop_sell,
       r.sell_short,
       r.sell_stop,
       r.buy_os,
       r.stop_buy,
       check_long_profit ()as tst
       FROM
         public.thesheet_dailystats s,
         public.thesheet_recommendation r,
         public.thesheet_onepair
       WHERE
         s.one_pair_id = thesheet_onepair.id AND
         s.the_date = r.the_date_time::date AND
         r.one_pair_id = thesheet_onepair.id
       ORDER BY
         r.the_date_time DESC,
         thesheet_onepair.id ASC;


check_long_profit is the function. I basically want to do some
calculations on this record and return some calculated fields.

I can't seem to figure out how to pass the row.

Here is my header for the function
create or replace function check_long_profit () returns integer AS $$

I know I am missing something easy.

Thanks