#property indicator_chart_window
#property indicator_buffers 1
#property indicator_color1 Gold
#property indicator_width1 2
//--- input parameters
extern int       Period_main=10;
extern int       Period_plus=20;

double dinMA[];
//+------------------------------------------------------------------+
//| Custom indicator initialization function                         |
//+------------------------------------------------------------------+
int init()
  {
//---- indicators
   SetIndexStyle(0,DRAW_LINE);
   IndicatorDigits(MarketInfo(Symbol(),MODE_DIGITS));
   SetIndexBuffer(0,dinMA);
//----
   return(0);
  }
//+------------------------------------------------------------------+
//| Custom indicator deinitialization function                       |
//+------------------------------------------------------------------+
int deinit()
  {
//----
   
//----
   return(0);
  }
//+------------------------------------------------------------------+
//| Custom indicator iteration function                              |
//+------------------------------------------------------------------+
int start()
  {
//----
   for (int i=0;i<Bars;i++)
   {double ma_main= iMA(NULL,0,Period_main,0,MODE_EMA,PRICE_CLOSE,i);
    double ma_plus= iMA(NULL,0,Period_plus,0,MODE_EMA,PRICE_CLOSE,i);
    dinMA[i]=ma_main*2-ma_plus;
   }
//----
   return(0);
  }
//+------------------------------------------------------------------+