maxminchannelwithslope

//+------------------------------------------------------------------+
//|simple max - min channel with slope                               +
//+------------------------------------------------------------------+
#property copyright "fajuzi@yahoo.it 2015"
#property description "simple max - min channel with ema slope"
#property indicator_chart_window
#property indicator_buffers 3
//#property indicator_color1 Gold
#property indicator_color2 Blue
#property indicator_color3 Blue
//string short_name;
//--- external var
input int      barre=20;//bars for calculation min max
input double   ratio=4.0;//ratio ema period / bars
input double   xslope=1.0;//slope adjustment
//-----global var
double cosemap,emap,xslp,pendenzaxslp;
//---- buffers
double /*mediana[],*/pendenza[],bandasu[],bandaju[];
//+------------------------------------------------------------------+
//| Custom indicator initialization function                         |
//+------------------------------------------------------------------+
int init()
  {
   xslp=xslope*0.5;//adjustment of slope
   emap=barre*ratio;//period
   cosemap=(emap+1.0)/2.0;//constant
//---- indicators
   SetIndexStyle(1,DRAW_LINE,STYLE_SOLID);
   SetIndexStyle(2,DRAW_LINE,STYLE_SOLID);
//SetIndexStyle(3,DRAW_LINE,STYLE_SOLID);
   SetIndexBuffer(0,pendenza);
   SetIndexBuffer(1,bandasu);
   SetIndexBuffer(2,bandaju);
//SetIndexBuffer(3,mediana);
   IndicatorDigits(5);
   string short_name="donpen2("+IntegerToString(barre)+","+DoubleToString(ratio,2)+")";
   IndicatorShortName(short_name);
//SetIndexLabel(0,"middle");
   SetIndexLabel(1,"up");
   SetIndexLabel(2,"down");
   return(1);
  }
//+------------------------------------------------------------------+
//| Custom indicator iteration function                              |
//+------------------------------------------------------------------+
int start()
  {
   int pos=Bars-5;
   int counted_bars=IndicatorCounted();
//---- check for possible errors
   if(counted_bars<0) return(-1);
//---- last counted bar will be recounted
   if(counted_bars>0) pos=Bars-counted_bars-1;
   else
     {
      pendenza[pos+1]=0.0;
     }
   while(pos>=0)
     {
      pendenza[pos]=pendenza[pos+1]+(High[pos]+Low[pos]-High[pos+1]-Low[pos+1]-pendenza[pos+1])/cosemap;
      pendenzaxslp=pendenza[pos]*xslp;

      switch(pos+1-iHighest(Symbol(),Period(),MODE_HIGH,barre,pos))
        {
         case 0 : bandasu[pos+1]=High[pos+1]; break;
         default : bandasu[pos+1]=bandasu[pos+2]+pendenzaxslp;
        }
      switch(pos+1-iLowest(Symbol(),Period(),MODE_LOW,barre,pos))
        {
         case 0 : bandaju[pos+1]=Low[pos+1]; break;
         default : bandaju[pos+1]=bandaju[pos+2]+pendenzaxslp;
        }
      //mediana[pos+1]=(bandasu[pos+1]+bandaju[pos+1])*0.5;
      pos--;
     }
   bandasu[0]=bandasu[1]+pendenzaxslp;
   bandaju[0]=bandaju[1]+pendenzaxslp;
//mediana[0]=mediana[1]+pendenzaxslp;
//----
   return(0);
  }
//+------------------------------------------------------------------+