MATLAB need help in writing mean absolute error code

Question

I am using this code but it is throwing error- Undefined function 'symsum' for input arguments of type 'double'.

%Mean Absolute Error;

Func=zeros(size(V,1),1);

E_mae=zeros(size(V,1),1);

Func(i,1)=abs(Iref(i,1)-Icalc(i,1))/size(V,1);

E_mae(i,1)= symsum(Func(i,1),i,1,size(V));

Answer 1

The function symsum(.) requires i to be a symbolic variable.