Chande_Kroll_Stop_v1

//+------------------------------------------------------------------+
//|                                         Chande_Kroll_Stop_v1.mq4 |
//|                                  Copyright © 2006, Forex-TSD.com |
//|                         Written by IgorAD,igorad2003@yahoo.co.uk |   
//|            http://finance.groups.yahoo.com/group/TrendLaboratory |                                      
//+------------------------------------------------------------------+
#property copyright "Copyright © 2006, Forex-TSD.com "
#property link      "http://www.forex-tsd.com/"

#property indicator_chart_window
#property indicator_buffers 2
#property indicator_color1 Blue
#property indicator_color2 Red


//---- input parameters
extern int    Length    =20;
extern int    ATRPeriod =10;
extern double Kv        = 3;

//---- indicator buffers
double UpTrend[];
double DnTrend[];
double smin[];
double smax[];
//+------------------------------------------------------------------+
//| Custom indicator initialization function                         |
//+------------------------------------------------------------------+
  int init()
  {
   string short_name;
//---- indicator line
   SetIndexStyle(0,DRAW_LINE);
   SetIndexStyle(1,DRAW_LINE);
   IndicatorBuffers(4);
   SetIndexBuffer(0,UpTrend);
   SetIndexBuffer(1,DnTrend);
   SetIndexBuffer(2,smin);
   SetIndexBuffer(3,smax);
//---- name for DataWindow and indicator subwindow label
   short_name="Chande Kroll Stop("+Length+","+ATRPeriod+","+Kv+")";
   IndicatorShortName(short_name);
   SetIndexLabel(0,"UpTrend");
   SetIndexLabel(1,"DnTrend");
//----
   SetIndexDrawBegin(0,Length);
   SetIndexDrawBegin(1,Length);
//----
   return(0);
  }

//+------------------------------------------------------------------+
//| Chande_Kroll_Stop_v1                                             |
//+------------------------------------------------------------------+
int start()
  {
   
   int shift,limit, counted_bars=IndicatorCounted();
   
   if ( counted_bars > 0 )  limit=Bars-counted_bars;
   if ( counted_bars < 0 )  return(0);
   if ( counted_bars ==0 )  limit=Bars-Length-1; 
     
	for(shift=limit;shift>=0;shift--) 
   {	
   smin[shift]=High[Highest(NULL,0,MODE_HIGH,ATRPeriod,shift)] - Kv*iATR(NULL,0,ATRPeriod,shift); 
   smax[shift]=Low [Lowest (NULL,0,MODE_LOW ,ATRPeriod,shift)] + Kv*iATR(NULL,0,ATRPeriod,shift);      
   
   UpTrend[shift] = -10000000; 
   DnTrend[shift] =  10000000;
     
      for (int i = Length-1;i>=0;i--)
      {
      UpTrend[shift] = MathMax( UpTrend[shift], smin[shift+i]); 
      DnTrend[shift] = MathMin( DnTrend[shift], smax[shift+i]);
      }
   }
	return(0);	
 }