Error: "Attempted to access stream(3); index out of bounds because numel(stream)=2."

Hi all,

I am trying to write a minimization function. I have the function below and am then using it with fminunc to minimize. However, I keep getting the error above. Any advice?

-Kyle

function E2 = hw07p7func(stream)

s1 = stream(1) ; s2 = stream(2) ; s3 = stream(3) ; s4 = stream(4) ;

r1 = s1-.996*s3-.196*s4 ; r2 = .99*s2-.8*s4 ; r3 =.01*s2-.04*s3-.04*s4 ;

E2 = (r1.^2 + r2.^2 +r3^2)