Zig-Hi Zap-Lo: Unexpected result

AFL Programming
1

Hi

I am experimenting with the "Zig-Hi Zap-Lo" code from the member's area.

I made very slight modifications, just to allow for smaller values of the zig %, and also to display the zig value on the title.

Notice that the currect bar is a HIGH of the ZigHiZapLow line, but it toutches the LOW of the bar. Same thing happens on the next high.

zighilo

My first impression is that this happens because of the prolonged downtrend.

Here is the code:

/*
   Zig-Hi-Zag-Lo

   To use to plot the true Peak High and Trough Low
   for study of chart pattern, to create trading system

   Modified from http://trader.online.pl/MSZ/e-w-ZigZag_HiLo.html

   By TohMz 
*/
pr=Param("ZigZag change amount", 0.01, 0.01,100,0.01);

pk=PeakBars(H,pr)==0;
tr=TroughBars(L,pr)==0;

zzHi=Zig(H,pr);
zzLo=Zig(L,pr);
Avg=(zzHi+zzLo)/2;

x=IIf(pk,zzHi,IIf(tr,zzLo,IIf(Avg>Ref(Avg,-1),H,L)));
zzHiLo=Zig(x,pr);

Plot( zzHiLo, "zzHiLo", ParamColor("Color",colorRed), ParamStyle("Style"));

//-- Delete below, to allow attach to any price chart
_N(Title = StrFormat("{{NAME}}- {{INTERVAL}} {{DATE}} O= %g, H= %g, L= %g, C= %g (%.1f%%) V= " +WriteVal( V, 1.0 ) +"\n{{VALUES}}", O, H, L, C, SelectedValue( ROC( C, 1 )) ));
PriceStyle = GetPriceStyle();
PriceStyleOpt = ParamStyle("Style") | PriceStyle;

if (PriceStyle==styleCandle)
   Plot( C, "", colorBlack,  PriceStyleOpt); 
else
   Plot( C, "", IIf( Close >= Ref(C, -1), colorBlue, colorRed ), PriceStyleOpt);

Moderator comment: The formula is supposedly to be based on MS code http://trader.online.pl/MSZ/e-w-ZigZag_HiLo.html

1 Like
2 
// AFL code by Edward Pottasch, Feb 2013

SetChartOptions(0,chartShowArrows|chartShowDates);
_N(Title = StrFormat("{{NAME}} - {{INTERVAL}} {{DATE}} Open %g, Hi %g, Lo %g, Close %g (%.1f%%) {{VALUES}}", O, H, L, C, SelectedValue( ROC( C, 1 ) ) ));
Plot( C, "Close", ParamColor("Color", colorBlack ), styleNoTitle | ParamStyle("Style") | GetPriceStyle() ); 
SetChartBkGradientFill(ColorRGB(200,222,9),ColorRGB(200,229,9));



procedure alternate_proc(pk,tr,sumpk,sumtr)
{
global pkg;
global trg;

pkg=pk;trg=tr;
idxpk=0;
idxtr=0;
flgtr=0;
flgpk=0;

for(i=1;i<BarCount;i++)
{
	if(pk[i] AND sumpk[i]==1 AND !tr[i] AND flgpk==0)
	{
		idxpk=i;
		flgtr=0;
	}
	else if( (pk[i] AND sumpk[i]>1 AND !tr[i]) OR (pk[i] AND flgpk==1) )
	{
		if(H[i]>=H[idxpk])
		{
			pkg[idxpk]=0;
			idxpk=i;
			flgpk=0;
		}
		else if(H[i]<H[idxpk])
		{
			pkg[i]=0;
			flgpk=0;
		}
	}
	else if(tr[i] AND sumtr[i]==1 AND !pk[i] AND flgtr==0)
	{
		idxtr=i;
		flgpk=0;
	}
	else if( (tr[i] AND sumtr[i]>1 AND !pk[i]) OR (tr[i] AND flgtr==1) )
	{
		if(L[i]<=L[idxtr])
		{
			trg[idxtr]=0;
			idxtr=i;
			flgtr=0;
		}
		else if(L[i]>L[idxtr])
		{
			trg[i]=0;
			flgtr=0;
		}
	}
	else if(pk[i] AND tr[i])
	{
		if(sumpk[i-1]>sumtr[i-1])
		{
			pkg[i]=0;
			flgtr=1;
			idxtr=i;
		}
		else if(sumtr[i-1]>sumpk[i-1])
		{
			trg[i]=0;
			flgpk=1;
			idxpk=i;
		}
	}
}
}

//SetBarsRequired(sbrAll,sbrAll);
//RequestTimedRefresh(0.1,True); 
xx=BarIndex();x=xx;Lx=LastValue(x);
nbar=Param("N Pivot Bars",5,2,50,1); 
tf=Param("Time Frame (min)",5,1,1440,1);tfrm=in1Minute*tf;
CleanPivots=ParamToggle("Use Clean Pivots","Off|On",1);
PivotSymmetry=ParamToggle("Use Symmetric Pivots","Off|On",0);
dispLabels=ParamToggle("Display Labels","Off|On",1);

TimeFrameSet(tfrm); 
if(PivotSymmetry)
{
	fc=1;
	pk=H>Ref(HHV(H,nbar*fc),-1) AND Ref(HHV(H,nbar),nbar)<=H;
	tr=L<Ref(LLV(L,nbar*fc),-1) AND Ref(LLV(L,nbar),nbar)>=L;
}
else
{
	fc=2;
	pk=H>Ref(HHV(H,nbar*fc),-1) AND Ref(HHV(H,nbar),nbar)<=H;
	tr=L<Ref(LLV(L,nbar*fc),-1) AND Ref(LLV(L,nbar),nbar)>=L;
}

px0=ValueWhen(pk,x,0); tx0=ValueWhen(tr,x,0);
px1=ValueWhen(pk,x,1); tx1=ValueWhen(tr,x,1);
px2=ValueWhen(pk,x,2); tx2=ValueWhen(tr,x,2);
px3=ValueWhen(pk,x,3); tx3=ValueWhen(tr,x,3);
ph0=ValueWhen(pk,H,0); tl0=ValueWhen(tr,L,0);
ph1=ValueWhen(pk,H,1); tl1=ValueWhen(tr,L,1);
ph2=ValueWhen(pk,H,2); tl2=ValueWhen(tr,L,2);
ph3=ValueWhen(pk,H,3); tl3=ValueWhen(tr,L,3);

sumpk=Sum(pk,BarsSince(tr));"sumpk: " +WriteVal(Sumpk);
sumtr=Sum(tr,BarsSince(pk));"sumtr: " +WriteVal(Sumtr);

if(CleanPivots)
{

	alternate_proc(pk,tr,sumpk,sumtr);
	pk=pkg;
	tr=trg;
	
	px0=ValueWhen(pk,x,0); tx0=ValueWhen(tr,x,0);
	px1=ValueWhen(pk,x,1); tx1=ValueWhen(tr,x,1);
	px2=ValueWhen(pk,x,2); tx2=ValueWhen(tr,x,2);
	px3=ValueWhen(pk,x,3); tx3=ValueWhen(tr,x,3);	
	ph0=ValueWhen(pk,H,0); tl0=ValueWhen(tr,L,0);
	ph1=ValueWhen(pk,H,1); tl1=ValueWhen(tr,L,1);
	ph2=ValueWhen(pk,H,2); tl2=ValueWhen(tr,L,2);
	ph3=ValueWhen(pk,H,3); tl3=ValueWhen(tr,L,3);	
}
pkh=IIf(pk,H,Null);
trl=IIf(tr,L,Null);
TimeFrameRestore();
fact=Nz(Max(tfrm/60,Interval()/60)/(Interval()/60));
if(fact==0)fact=1;
Lkbk=Nz(tfrm/Interval());
if(Lkbk>1)
{
	pk=TimeFrameExpand(pk,tfrm,expandFirst);
	pkh=TimeFrameExpand(pkh,tfrm,expandFirst);
	pkhs=IIf(!IsEmpty(pkh),1,0);pkhs=pkhs-Ref(pkhs,-1);
	pk=pk AND H==pkh;
	cond1=Sum(pk,BarsSince(pkhs==1)+1)==1 AND pk;
	pk=pk AND cond1;
	
	tr=TimeFrameExpand(tr,tfrm,expandFirst);	
	trl=TimeFrameExpand(trl,tfrm,expandFirst);
	trls=IIf(!IsEmpty(trl),1,0);trls=trls-Ref(trls,-1);
	tr=tr AND L==trl;
	cond1=Sum(tr,BarsSince(trls==1)+1)==1 AND tr;
	tr=tr AND cond1;
	
	px0=ValueWhen(pk,x,0); tx0=ValueWhen(tr,x,0);
	px1=ValueWhen(pk,x,1); tx1=ValueWhen(tr,x,1);
	px2=ValueWhen(pk,x,2); tx2=ValueWhen(tr,x,2);
	px3=ValueWhen(pk,x,3); tx3=ValueWhen(tr,x,3);
	ph0=ValueWhen(pk,H,0); tl0=ValueWhen(tr,L,0);
	ph1=ValueWhen(pk,H,1); tl1=ValueWhen(tr,L,1);
	ph2=ValueWhen(pk,H,2); tl2=ValueWhen(tr,L,2);
	ph3=ValueWhen(pk,H,3); tl3=ValueWhen(tr,L,3);
}

ll=tr AND tl1<tl2;
hl=tr AND tl1>tl2;
hh=pk AND ph1>ph2;
lh=pk AND ph1<ph2;
dt=pk AND ph1==ph2;
db=tr AND tl1==tl2;

ll_h=IIf(ll,1,0);
hl_h=IIf(hl,2,0);
hh_h=IIf(hh,3,0);
lh_h=IIf(lh,4,0);
dt_h=IIf(dt,5,0);
db_h=IIf(db,6,0);

combi=ll_h+hl_h+lh_h+hh_h+dt_h+db_h;

t0=ValueWhen(combi,combi,0);
t1=ValueWhen(combi,combi,1);
t2=ValueWhen(combi,combi,2);
t3=ValueWhen(combi,combi,3);
t4=ValueWhen(combi,combi,4);
t5=ValueWhen(combi,combi,5);

//at pk
pAx=ValueWhen(pk,tx1);pAy=ValueWhen(pk,tl1);
pBx=ValueWhen(pk,px1);pBy=ValueWhen(pk,ph1);
// at tr
tAx=ValueWhen(tr,px1);tAy=ValueWhen(tr,ph1);
tBx=ValueWhen(tr,tx1);tBy=ValueWhen(tr,tl1);

GraphXSpace=5;SetChartBkColor(ColorRGB(0,0,0));SetChartOptions(0,chartShowDates);
SetBarFillColor(IIf(C>O,colorGreen,IIf(C<=O,colorRed,colorLightGrey)));
Plot(C,"Price",IIf(C>O,colorDarkGreen,IIf(C<=O,colorDarkRed,colorLightGrey)),64,0,0,0,0);
Plot(pkh,"",colorWhite,styleThick,0,0,0,-1);
Plot(trl,"",colorWhite,styleThick,0,0,0,-1);
PlotShapes(shapeSmallCircle*tr,IIf(Lx-ValueWhen(tr,x)>nbar*fact,ColorRGB(0,100,0),colorWhite),0,L,-10);
PlotShapes(shapeSmallCircle*pk,IIf(Lx-ValueWhen(pk,x)>nbar*fact,ColorRGB(255,0,0),colorWhite),0,H,10);

qq=Interval()/60;
if(qq < 60){tf=" min";tt=qq;}
else if(qq >= 60 AND qq < 1440){tf=" hrs";tt=qq/60;}
else if(qq >= 1440){tf=" days";tt=(qq/60)/24;}
qq=Max(tfrm/60,Interval()/60);
if(qq < 60){tfa=" min";tta=qq;}
else if(qq >= 60 AND qq < 1440){tfa=" hrs";tta=qq/60;}
else if(qq >= 1440){tfa=" days";tta=(qq/60)/24;}

Title =Name() + 
"\nNbar: " + nbar + 
"\nChart TF: " + tt + tf + 
"\nTrend TF: " + tta + tfa;

abcdy_up=27;
abcdy_dn=15;
function GetVisibleBarCount() 
{
	lvb=Status("lastvisiblebar");
	fvb=Status("firstvisiblebar");
	return Min(lvb-fvb,BarCount-fvb);
} 
function GfxConvertPixelsToBarX(Pixels)
{
	lvb=Status("lastvisiblebar");
	fvb=Status("firstvisiblebar");
	pxchartleft=Status("pxchartleft");
	pxchartwidth=Status("pxchartwidth");
	fac=pxchartwidth/Pixels;
	bar=(lvb-fvb)/fac;
	return Nz(bar);
} 
function GfxConvertPixelToValueY(Pixels) 
{
	local Miny,Maxy,pxchartbottom,pxchartheight;
	Miny=Status("axisminy");
	Maxy=Status("axismaxy");
	pxchartbottom=Status("pxchartbottom");
	pxchartheight=Status("pxchartheight");
	fac=pxchartheight/Pixels;
	Value=(Maxy-Miny)/fac;
	return Nz(Value);
} 
function GfxConvertBarToPixelX(bar) 
{ 
	lvb=Status("lastvisiblebar"); 
	fvb=Status("firstvisiblebar"); 
	pxchartleft=Status("pxchartleft"); 
	pxchartwidth=Status("pxchartwidth"); 
	return Nz(pxchartleft+bar*pxchartwidth/(lvb-fvb+1)); 
} 
function GfxConvertValueToPixelY(value) 
{
	local Miny,Maxy,pxchartbottom,pxchartheight; 
	Miny=Status("axisminy");
	Maxy=Status("axismaxy");
	pxchartbottom=Status("pxchartbottom");
	pxchartheight=Status("pxchartheight");
	return Nz(pxchartbottom-floor(0.5+(Value-Miny)*pxchartheight/(Maxy-Miny))); 
} 
AllVisibleBars=GetVisibleBarCount();
fvb=Status("firstvisiblebar");
abcdy_up=GfxConvertPixelToValueY(abcdy_up);
abcdy_dn=GfxConvertPixelToValueY(abcdy_dn);

for(i=0;i<AllVisibleBars;i++) 
{
	if(ll[i+fvb] AND dispLabels)
	{
		lvix=i+fvb;GfxSelectFont("Tahoma",8,500); GfxSetBkMode(1); 
		GfxSetTextColor(colorYellow);GfxTextOut("LL",GfxConvertBarToPixelX(i)-3,GfxConvertValueToPixelY(L[lvix]-abcdy_dn)); 
		GfxSetTextColor(colorYellow);GfxTextOut(""+L[lvix],GfxConvertBarToPixelX(i)-3,GfxConvertValueToPixelY(L[lvix]-2*abcdy_dn)); 
	}
	if(hl[i+fvb] AND dispLabels)
	{
		lvix=i+fvb;GfxSelectFont("Tahoma",8,500); GfxSetBkMode(1); 
		GfxSetTextColor(colorYellow);GfxTextOut("HL",GfxConvertBarToPixelX(i)-3,GfxConvertValueToPixelY(L[lvix]-abcdy_dn)); 
		GfxSetTextColor(colorYellow);GfxTextOut(""+L[lvix],GfxConvertBarToPixelX(i)-3,GfxConvertValueToPixelY(L[lvix]-2*abcdy_dn)); 
	}	
	if(db[i+fvb] AND dispLabels)
	{
		lvix=i+fvb;GfxSelectFont("Tahoma",8,500); GfxSetBkMode(1); 
		GfxSetTextColor(colorYellow);GfxTextOut("DB",GfxConvertBarToPixelX(i)-3,GfxConvertValueToPixelY(L[lvix]-abcdy_dn)); 
		GfxSetTextColor(colorYellow);GfxTextOut(""+L[lvix],GfxConvertBarToPixelX(i)-3,GfxConvertValueToPixelY(L[lvix]-2*abcdy_dn)); 
	}		
	if(hh[i+fvb] AND dispLabels)
	{
		lvix=i+fvb;GfxSelectFont("Tahoma",8,500); GfxSetBkMode(1); 
		GfxSetTextColor(colorYellow);GfxTextOut("HH",GfxConvertBarToPixelX(i)-5,GfxConvertValueToPixelY(H[lvix]+abcdy_up)); 
		GfxSetTextColor(colorYellow);GfxTextOut(""+H[lvix],GfxConvertBarToPixelX(i)-5,GfxConvertValueToPixelY(H[lvix]+1.57*abcdy_up)); 
	}	
	if(lh[i+fvb] AND dispLabels)
	{
		lvix=i+fvb;GfxSelectFont("Tahoma",8,500); GfxSetBkMode(1); 
		GfxSetTextColor(colorYellow);GfxTextOut("LH",GfxConvertBarToPixelX(i)-5,GfxConvertValueToPixelY(H[lvix]+abcdy_up));
		GfxSetTextColor(colorYellow);GfxTextOut(""+H[lvix],GfxConvertBarToPixelX(i)-5,GfxConvertValueToPixelY(H[lvix]+1.57*abcdy_up));
	}	
	if(dt[i+fvb] AND dispLabels)
	{
		lvix=i+fvb;GfxSelectFont("Tahoma",8,500); GfxSetBkMode(1); 
		GfxSetTextColor(colorYellow);GfxTextOut("DT",GfxConvertBarToPixelX(i)-5,GfxConvertValueToPixelY(H[lvix]+abcdy_up)); 
		GfxSetTextColor(colorYellow);GfxTextOut(""+H[lvix],GfxConvertBarToPixelX(i)-5,GfxConvertValueToPixelY(H[lvix]+1.57*abcdy_up)); 
	}		
	if(pk[i+fvb])
	{
		lvix=i+fvb;
		Plot(LineArray(pAx[lvix],pAy[lvix],pBx[lvix],pBy[lvix],0,True ),"",ColorRGB(0,0,200),styleThick);
	}
	if(tr[i+fvb])
	{
		lvix=i+fvb;
		Plot(LineArray(tAx[lvix],tAy[lvix],tBx[lvix],tBy[lvix],0,True ),"",ColorRGB(200,0,0),styleThick);
	}	
}
_SECTION_END();
3

yikes ..... that is old code, I do not recommend that code.

the answer to bobs question in my opinion is that the Zig line you calculate does not correspond to the peaks and troughs you calculate.

simply add these 2 lines to the bottom of the code and you see what I mean:

PlotShapes( shapeSmallCircle * tr, ColorRGB( 0, 255, 0 ), 0, L, -10 );
PlotShapes( shapeSmallCircle * pk, ColorRGB( 255, 0, 0 ), 0, H, 10 );
6