function goTo(target) {
          if (target >= smax || target == snum) return;
          go(target - snum);
  }
  
  function subgo(step) {
          if (step > 0) {
                  removeClass(incrementals[snum][incpos - 1],'current');
                  removeClass(incrementals[snum][incpos], 'incremental');
                  addClass(incrementals[snum][incpos],'current');
                  incpos++;
          } else {
                  incpos--;
                  removeClass(incrementals[snum][incpos],'current');
                  addClass(incrementals[snum][incpos], 'incremental');
                  addClass(incrementals[snum][incpos - 1],'current');
          }
  }