3/8 EMA CROSSOVER for Amibroker exit signals

Algos, strategies, code
1

For below script I want to add exit signal after Buy as well exit signal after Sell.

_SECTION_BEGIN("Price");
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() ); 
_SECTION_END();

_SECTION_BEGIN(“ema_crossover”);

x = EMA(Close,3);

y = EMA(Close,8);

Plot(EMA(Close,3),"",colorRed,styleLine);

Plot(EMA(Close,8),"",colorDarkGreen,styleLine);


Buy=Cross(x,y);

PlotShapes(shapeUpArrow*Buy,colorGreen);

XR=(EMA(Close,3) * (2 / 6 - 1) - EMA(Close,8) * (2 / 11 - 1)) / (2 / 6 - 2 / 11);

Title = Name() + " " + Date()+" " + EncodeColor( colorBlue ) +"3/8 EMA " +EncodeColor( colorRed )
  • " O " + O + " H " + H + " L " + L + " C "+ C + “\n”;

Sell=Cross(y,x);
PlotShapes(shapeDownArrow*Sell,colorRed);
AlertIf( Sell, “SOUND C:\Windows\Media\chord.wav”, “Audio alert”, 2 );
XR=(EMA(Close,8) * (2 / 6 - 1) - EMA(Close,3) * (2 / 11 - 1)) / (2 / 6 - 2 / 11);
Title = Name() + " " + Date()+" " + EncodeColor( colorBlue ) +"3/8 EMA " +EncodeColor( colorRed )

  • " O " + O + " H " + H + " L " + L + " C "+ C + “\n”;

_SECTION_END();

Source: http://www.wisestocktrader.com/indicators/2155-3-8-ema-crossover
Please help, thanks.
2

you can define Short and Cover with the required condition

Example 

Cover = Buy* ROC(Close,12,True);

Short = Sell* ROC(Close,12,True);
3

For above example will it be like:
Cover = Buy* ROC(Close,3,True);
Short = Sell* ROC(Close,8,True);
I am not getting what is Buy* ROC(Close,12,True);