//+------------------------------------------------------------------+
//|                                        Custom Moving Average.mq4 |
//|                      Copyright © 2004, MetaQuotes Software Corp. |
//|                                       http://www.metaquotes.net/ |
//+------------------------------------------------------------------+
#property copyright "Copyright © 2004, MetaQuotes Software Corp."
#property link      "http://www.metaquotes.net/"

//#property indicator_chart_window
#property indicator_separate_window
#property indicator_buffers 1
#property indicator_color1 Red
//---- indicator parameters
extern int MA_Period=34;
extern int MA_Shift=0;
extern int MA_Method=0;
//---- indicator buffers
double ExtMapBuffer[];
//----
int ExtCountedBars=0;
//+------------------------------------------------------------------+
//| Custom indicator initialization function                         |
//+------------------------------------------------------------------+
int init()
  {
   int    draw_begin;
   string short_name;
//---- drawing settings
   SetIndexStyle(0,DRAW_LINE);
   SetIndexShift(0,MA_Shift);
   IndicatorDigits(MarketInfo(Symbol(),MODE_DIGITS));
   if(MA_Period<2) MA_Period=34;
   draw_begin=MA_Period-1;
//---- indicator short name
    short_name="EMA(";
    IndicatorShortName(short_name+MA_Period+")");
   SetIndexDrawBegin(0,draw_begin);
//---- indicator buffers mapping
   SetIndexBuffer(0,ExtMapBuffer);
//---- initialization done
   return(0);
  }
//+------------------------------------------------------------------+
//|                                                                  |
//+------------------------------------------------------------------+
int start()
  {
   if(Bars<=MA_Period) return(0);
   ExtCountedBars=IndicatorCounted();
//---- check for possible errors
   if (ExtCountedBars<0) return(-1);
//---- last counted bar will be recounted
   if (ExtCountedBars>0) ExtCountedBars--;
//----
   slope();
//---- done
   return(0);
  }

void slope()
{
   double pr=2.0/(MA_Period+1);
   int    pos=Bars-2;
   if(ExtCountedBars>2) pos=Bars-ExtCountedBars-1;
//---- main calculation loop
   ExtMapBuffer[pos]=NULL;
   while(pos>=0)
   {
      if(pos==Bars-2) 
      {
         ExtMapBuffer[pos+1]=NULL;
      }
      ExtMapBuffer[pos]= -iMA(NULL, 0, 34, 0, MODE_EMA, PRICE_CLOSE,pos)+ iMA(NULL, 0, 34, 0, MODE_EMA, PRICE_CLOSE,pos+2);
 	   if (ExtMapBuffer[pos]>1 )
 	   {
 	      ExtMapBuffer[pos+1]=NULL;
      }
      ExtMapBuffer[pos] = ExtMapBuffer[pos];
 	   pos--;
   }
}