Here is the ITrend formula with an Initialization addition that
reduces the long convergence time for very low values of Alpha.
It presents also the addition of a trigger.
Code:
{=======================}
{Need the ADSI's DLL from www.thedml.com}
Pc:=
Input("Price Code=C,Med,Typ,WMA4 [1-4]",1,4,3);
Ap:=Input("Alpha Value",0.001,1,0.0198);
ILen:=Input("Initialization Period",10,1000,60);
WMA4:=Mov(Typ(),4,W);
Dlt:=(0.33-Ap)/ILen;
Apn:=If(Cum(1)<=ILen,0.33-(Cum(1)*Dlt),Ap);
Pr:=
If(Pc=1,C,
If(Pc=2,MP(),
If(Pc=3,Typ(),WMA4)));
Ind:=
ExtFml("ADSI.ITrend",Pr,Apn);
Trig:=2*Ind-Ref(Ind,-2);
Ind;
Trig;
{=================}