Function outputs a 1x2 matrix, yet I can't append that matrix to another matrix.

function prop(f,u,q,sq)

%Define stuff
SQ=[];       
Q=[];
g=size(q);

%Evaluation of f with q
Q=subs(f,u,q);

%Uncertainty
for h=1:g(1,2);
    Sq=subs(((diff(f,u(1,h)))^2*sq(1,h)^2),u,q);
    SQ=sqrt(sum([SQ Sq]));
end
[Q SQ]
end

The function requires for f a symbolic function, u a row vector with all the variables being used in f, q a row vector that contains values for these variables and sq also some values. (so a symbolic function with n variables and then three 1 x n row vectors). For example f=u1+u2, u=[u1 u2], q=[1 2] and sq=[0.1 0.2].

It outputs a 1x2 matrix, yet when I try

A=[]
A=[A prop(f,u,[1 2],[0.1 0.2])]

I get "??? Error using ==> prop Too many output arguments."

How can I fix this? I need the output of this function to be used in another function which uses this function multiple times for varying q vectors (and then adding the varying output 1x2 vectors to one big vector)

Answer 1

[Daniel Shub]

You need to change the first line to:

function A = prop(f,u,q,sq)

and the second to last line to

A = [Q SQ]

You can use any name you want for A.

Depending on what Q and SQ are (potentially they are symbolic), then you may need to initialize A to be something else in your main script

A = sym.empty(0, 2);