Undefined function 'symsum' for input arguments of type 'double'

Can someone explain me how can I correct this error "Undefined function ' symsum' for input arguments of type 'double'"

function [ yij ] = SPCmethod(yij,w)
          sym n;
          rep = 100;
          for i = 1:w
              yij(i) = mean (symsum(yij,i,1,rep))/rep
          end

[Walter Roberson]

What is the data type and size() of yij being passed in?

What is it that is to be summed?

symsum() will give back a scalar if its first parameter is scalar, so it is not immediately clear why you want to mean() the result.

[Laura Barroso]

I have to apply this sum to a M/M/1 queuing server simulation. It is not scalar, it's a matrix. I have another function that runs this into MM1, so the size of yij depends on the number of replicas of M/M/1 queuing server simulation.

[Walter Roberson]

What is the data class of yij? You mention it is a matrix, but is it a matrix of double or a matrix of symbolic constants or a matrix of formulae?

Answer 1

[Walter Roberson]

For numeric array yji,

y_bar_i = mean(yji);

There should not be any loop: your other function that runs this is doing the looping.

There would only be a loop at the level that is generating multiple yji matrices.