Arrow Sars for Amibroker (AFL)

_SECTION_BEGIN("_SARS");
acc = Param("Acceleration", 0.02, 0, 1, 0.001 );
accm = Param("Max. acceleration", 0.2, 0, 1, 0.001 );
dynamic_color = IIf( SAR() > H, colorRed, colorGreen ); 
Plot( SAR( acc, accm ), "_SARS", dynamic_color,styleDots | styleNoLine);
Plot( Close, "Price", colorBlue, styleBar );
Buy=Ref( High , -1 ) < Ref( SAR() , -1 ) AND Low>SAR();
Sell= Ref( Low , -1 )> Ref(SAR() , -1) AND High <SAR();
PlotShapes( Buy * shapeUpArrow + Sell * shapeDownArrow, IIf( Buy, colorGreen, colorRed ),0,IIf( Buy, L, H ),-10 );
_SECTION_END();