for i=1:64,
   j=221;
   if t64(j,i)>0,
      while t64(j,i)>0 && j>1,
         j = j-1;
      end
      last = t64(j+1,i);
      %t(1:j,i) = 0:(last/(length(t(1:j,i))-1)):last;
   else
      t64(:,i) = zeros(size(t(:,i)));
   end
end