how to calculate this

I need a help in this to find in matlab ∑_i∑_j[y_(i ) y_j √(a_i a_j e_i e_j )]

where only yi, yj are same component which are C1,C2,C3,C4 , and each components has a value of aj,aj,ei,ej , this sign ∑ came twice in here and I dont know how to expand this equation ..

Answer 1

[Image Analyst]

Wouldn't it just be

sumOfArray = 0;
for ii = 1 : lastI
  for jj = 1 : lastJ
    sumOfArray = sumOfArray + y(ii)*y(jj)*sqrt(a(ii)*a(jj)*e(ii)*e(jj));
  end
end

[Nasir Qazi]

a and e has different values in it