//+------------------------------------------------------------------+
//|                                                   StarcBands.mq4 |
//|                      Copyright © 2005, MetaQuotes Software Corp. |
//|                                       http://www.metaquotes.net/ |
//|                                                    Linuxser 2007 |
//+------------------------------------------------------------------+
#property copyright "Copyright © 2005, MetaQuotes Software Corp."
#property link      "http://www.metaquotes.net/"
//----
#property indicator_chart_window
#property indicator_buffers 3
#property indicator_color1 clrPurple
#property indicator_color2 clrBlue
#property indicator_color3 clrRed
//---- indicator parameters
extern int    BandsPeriod=6;
extern int    ATR=15;
extern double Multiplier = 2.0;
extern int    BandsShift = 0;
//---- buffers
double MovingBuffer[];
double UpperBuffer[];
double LowerBuffer[];
//+------------------------------------------------------------------+
//| Custom indicator initialization function                         |
//+------------------------------------------------------------------+
int init()
  {
//---- indicators
   SetIndexStyle(0,DRAW_LINE);
   SetIndexBuffer(0,MovingBuffer);
//---
   SetIndexStyle(1,DRAW_LINE);
   SetIndexBuffer(1,UpperBuffer);
//---
   SetIndexStyle(2,DRAW_LINE);
   SetIndexBuffer(2,LowerBuffer);
//----
   SetIndexDrawBegin(0,BandsPeriod+BandsShift);
   SetIndexDrawBegin(1,BandsPeriod+BandsShift);
   SetIndexDrawBegin(2,BandsPeriod+BandsShift);
//----
   return(0);
  }
//+------------------------------------------------------------------+
//| Bollinger Bands                                                  |
//+------------------------------------------------------------------+
int start()
  {
   int i,k,counted_bars=IndicatorCounted();
   double deviation;
   double sum,oldval,newres;
//----
   if(Bars<=BandsPeriod)
      return(0);
//---- initial zero
   if(counted_bars<1)
      for(i=1; i<=BandsPeriod; i++)
        {
         MovingBuffer[Bars-i]= EMPTY_VALUE;
         UpperBuffer[Bars-i] = EMPTY_VALUE;
         LowerBuffer[Bars-i] = EMPTY_VALUE;
        }
//----
   int limit=Bars-counted_bars;
   if(counted_bars>0)
      limit++;
   for(i=0; i<limit; i++)
      MovingBuffer[i]=iMA(NULL,0,BandsPeriod,BandsShift,
                          MODE_SMA,PRICE_CLOSE,i);
//----
   i=Bars-BandsPeriod+1;
   if(counted_bars>BandsPeriod-1)
      i=Bars-counted_bars-1;
   while(i>=0)
     {
      sum=0.0;
      k=i+BandsPeriod-2;
      oldval=MovingBuffer[i];
      while(k>=i)
        {
         newres=Close[k]-oldval;
         sum+=newres*newres;
         k--;
        }
      deviation=Multiplier*iATR(NULL,0,ATR,i); // MathSqrt(sum / BandsPeriod);
      UpperBuffer[i] = oldval + deviation;
      LowerBuffer[i] = oldval - deviation;
      i--;
     }
//----
   return(0);
  }
//+------------------------------------------------------------------+