[amibroker] help with this AFL needed

[przemyslawuk]

Why EMA(CLV,7) does not return a value?

CLV = ((Close - Low) - (High - Close)) / (High - Low) ;/calculates the
location of close in the current bar

COL=IIf(CLV>0.50,6,IIf(CLV<-0.50,4,3));
Plot(CLV,"Close Location Value",COL,2);

Plot( EMA(CLV,7),"EMA CLV",3);