[amibroker] Need Help with Formula

[blackcat54]

Having trouble with the following formula. If I calculate the value of adj and 
enter the numerical value into the z expression in place of adj, the formula 
works.

For example, if adj =10, and I enter 10 into the z expression 
"z=IIf(RBC>5,a,b+10);" the formula plots like I want. If I leave Adj in the z 
expression, the formula plots in a different (useless) way.

mp=IIf(C,(H+L+C)/3,(H+L)/2);

a=Ref(MA(mp,10),5);

b=EMA(mp,10);

adj=ValueWhen(rbc=6,a-b,1);

RBC=LastValue(Cum(1))-Cum(1)+1;

z=IIf(RBC>5,a,b+adj);

Plot(z,"Extended Avg 10-3",colorRed,styleLine);



Thanks