/*[[
Name := Forecast Oscillator
Author := Hapsa
Notes := Codes from LRI by Nick Bilak, beluck[at]ukr.net
Link :=http://finance.groups.yahoo.com/group/MetaTrader_Experts_and_Indicators
Separate Window := Yes
First Color := LightSkyBlue
First Draw Type := Line
First Symbol := 217
Use Second Data := Yes
Second Color := MediumSpringGreen
Second Draw Type := Line
Second Symbol := 218
]]*/

Inputs : Rperiod(15), t3_period(10), b(0.7);
Variables : shift(0), cnt(0), loopbegin(0), first(True), prevbars(0);
Variables : sum(0), length(0), i(0), mt(0), WT(0), vWT2(0),value(0), forecastosc(0), MA(0);
Variables : t3(0);
Variables : e1(0),e2(0),e3(0),e4(0),e5(0),e6(0),c1(0),c2(0),c3(0),c4(0);
Variables : n(0),w1(0),w2(0), b2(0),b3(0);
Variables : t3_fosc(0);

b2=b*b;
b3=b2*b;
c1=-b3;
c2=(3*(b2+b3));
c3=-3*(2*b2+b+b3);
c4=(1+3*b+b3+3*b2);
n=t3_period;

if n<1 then n=1;
n = 1 + 0.5*(n-1);
w1 = 2 / (n + 1);
w2 = 1 - w1;

SetLoopCount(0);
// initial checkings
	If RPeriod < 1 Then Exit;
	length=RPeriod;
	loopbegin = 206-length-1;
		For shift = loopbegin Downto 0 Begin
			sum=0;
				For i = length downTo 1 Begin
					sum = sum + (i-(length+1)/3)*Close[length-i+shift];
				End;
			WT=sum*6/(length*(length+1));
			
			forecastosc=(C[shift]-WT)/WT*100;
			
			SetIndexValue2(shift, 0);
  
  			e1 = w1*forecastosc + w2*e1;
  			e2 = w1*e1 + w2*e2;
  			e3 = w1*e2 + w2*e3;
  			e4 = w1*e3 + w2*e4;
  			e5 = w1*e4 + w2*e5;
  			e6 = w1*e5 + w2*e6;

 			t3_fosc = c1*e6 + c2*e5 + c3*e4 + c4*e3;
 

			SetIndexValue(shift,forecastosc);
			SetIndexValue2(shift,t3_fosc);
		End;