Settings=
{
   Name = "Example",
   line =
   {
      {
         Name = "Ex_line",
         Color = RGB(96, 96, 255),
         Type = TYPE_LINE,
         Width = 2
      }
   }
}

function OnCalc()
   local ind_l = 0
   return function(ind,FSettings)
      if ind<=1 then
         ind_l=0
      end
      if ind_l~=ind then
         ind_l=ind
         message (tostring(ind))
      end   
      return ind_l
   end
end

function Init()
   OC = OnCalc()
   return 1
end

function OnCalculate(index)
   return OC(index,Settings)
end