Force Index for Amibroker (AFL)

_SECTION_BEGIN("Force index");
ECw= EncodeColor(colorRed);
ECy= EncodeColor(colorBlue);

FI=EMA(((C-Ref(C,-1))*V),13);//

_N(Title = ECw+ "Force(13) Incex value:" +ECy+ FI);

Buy = Cross (FI,0);
Sell = Cross(0,FI);
aSell= Cross(0,FI);
shape = Buy * shapeUpArrow + Sell * shapeDownArrow;
PlotShapes( shape, IIf( Buy, colorYellow, colorPink ),0, IIf( Buy, L, H ) );
Buy = MACD( 12,26)-Signal(12,26,9)<0.01 AND Cross(FI,0);
aBuy = MACD( 12,26)-Signal(12,26,9)<0.01 AND Cross(FI,0);
PlotShapes( shapeUpArrow*Buy, colorGreen) ; 
Buy = Cross(MA( Close,10),MA(Close,50)) AND Cross(FI,0);
bBuy = Cross(MA( Close,10),MA(Close,50)) AND Cross(FI,0);
PlotShapes( shapeHollowSquare*Buy, colorBrightGreen) ; 

Sell = MACD( 12,26)-Signal(12,26,9)>0.03 AND Cross(0,FI);
bSell= MACD( 12,26)-Signal(12,26,9)>0.03 AND Cross(0,FI);
PlotShapes( shapeDownArrow*Sell, colorRed) ; 

//Filter = (aBuy OR bBuy) OR (aSell OR bSell);
Filter = (aBuy OR bBuy);

AddColumn(C, "Close");

Plot(FI,"FI",12,5);
Plot(0,"ZERO LINE",colorBlack,styleThick);
_SECTION_END();