ZigZag

//+——————————————————————+
//| Custom Moving Average.mq4 |
//| Copyright ?2005, MetaQuotes Software Corp. |
//| http://www.metaquotes.net/ |
//+——————————————————————+
#property copyright “Copyright ?2005, MetaQuotes Software Corp.”
#property link “http://www.metaquotes.net/”

#property indicator_chart_window
#property indicator_buffers 1
#property indicator_color1 Red
//—- indicator parameters
extern int ExtDepth=12;
extern int ExtDeviation=5;
extern int ExtBackstep=3;
//—- indicator buffers
double ExtMapBuffer[];
double ExtMapBuffer2[];

//+——————————————————————+
//| Custom indicator initialization function |
//+——————————————————————+
int init()
{
IndicatorBuffers(2);
//—- drawing settings
SetIndexStyle(0,DRAW_SECTION);
//—- indicator buffers mapping
SetIndexBuffer(0,ExtMapBuffer);
SetIndexBuffer(1,ExtMapBuffer2);
SetIndexEmptyValue(0,0.0);
ArraySetAsSeries(ExtMapBuffer,true);
ArraySetAsSeries(ExtMapBuffer2,true);
//—- indicator short name
IndicatorShortName(“ZigZag(“+ExtDepth+”,”+ExtDeviation+”,”+ExtBackstep+”)”);
//—- initialization done
return(0);
}
//+——————————————————————+
//| |
//+——————————————————————+
int start()
{
int shift, back,lasthighpos,lastlowpos;
double val,res;
double curlow,curhigh,lasthigh,lastlow;

for(shift=Bars-ExtDepth; shift>=0; shift–)
{
val=Low[Lowest(NULL,0,MODE_LOW,ExtDepth,shift)];
if(val==lastlow) val=0.0;
else
{
lastlow=val;
if((Low[shift]-val)>(ExtDeviation*Point)) val=0.0;
else
{
for(back=1; back<=ExtBackstep; back++)
{
res=ExtMapBuffer[shift+back];
if((res!=0)&&(res>val)) ExtMapBuffer[shift+back]=0.0;
}
}
}
ExtMapBuffer[shift]=val;
//— high
val=High[Highest(NULL,0,MODE_HIGH,ExtDepth,shift)];
if(val==lasthigh) val=0.0;
else
{
lasthigh=val;
if((val-High[shift])>(ExtDeviation*Point)) val=0.0;
else
{
for(back=1; back<=ExtBackstep; back++)
{
res=ExtMapBuffer2[shift+back];
if((res!=0)&&(res<val)) ExtMapBuffer2[shift+back]=0.0;
}
}
}
ExtMapBuffer2[shift]=val;
}

// final cutting
lasthigh=-1; lasthighpos=-1;
lastlow=-1; lastlowpos=-1;

for(shift=Bars-ExtDepth; shift>=0; shift–)
{
curlow=ExtMapBuffer[shift];
curhigh=ExtMapBuffer2[shift];
if((curlow==0)&&(curhigh==0)) continue;
//—
if(curhigh!=0)
{
if(lasthigh>0)
{
if(lasthigh<curhigh) ExtMapBuffer2[lasthighpos]=0;
else ExtMapBuffer2[shift]=0;
}
//—
if(lasthigh<curhigh || lasthigh<0)
{
lasthigh=curhigh;
lasthighpos=shift;
}
lastlow=-1;
}
//—-
if(curlow!=0)
{
if(lastlow>0)
{
if(lastlow>curlow) ExtMapBuffer[lastlowpos]=0;
else ExtMapBuffer[shift]=0;
}
//—
if((curlow<lastlow)||(lastlow<0))
{
lastlow=curlow;
lastlowpos=shift;
}
lasthigh=-1;
}
}

for(shift=Bars-1; shift>=0; shift–)
{
if(shift>=Bars-ExtDepth) ExtMapBuffer[shift]=0.0;
else
{
res=ExtMapBuffer2[shift];
if(res!=0.0) ExtMapBuffer[shift]=res;
}
}
}