Hello Victor,
My understanding is that your problem is with the syntax and your understanding of least mean square algorithm is correct.
Now answering your question y(n) and {sum(w.*xN)} are of different data types
When you try this in command window:
>> y = zeros(1,1000);
>> y(12)
ans =
0
so here y(n) is a scalar integer. But on the other side
>> w = zeros(1,100);
>> xN = x(100:-1:1);
>> ans = w.*xN;
Here w : 1x100
xN: 100x1
Now when you check the dimension of "ans" in workspace you will find it will 100x100 double array .This is because " .*" stands for element wise multiplication .When we multiply a 1x100 array with 100x1 array element wise it produce 100x100 array. To read further about element wise multiplication consider this document.
Similarly, when you do
>> ans = sum(w.*xN);
here "ans" would be 100x1 matrix as it performs row wise operation. Addition to that when we add curly bracket with it create cell array. So on the LHS we have a scaler and on the RHS we have Cell array, that's why that error is coming up.
