Undefined function 'sum' for input arguments of type 'struct'.

When I want to find a mean of a matrix A of size 1 by 18, the MATLAB give an error:

Undefined function 'sum' for input arguments of type 'struct'. Error in mean (line 30) y = sum(x,dim)/size(x,dim);

How can I solve this problem? Thanks.

Answer 1

[Geoff Hayes]

omid - the error message is telling you that the input to your sum function is a struct. Either one (or both) of x or dim is a struct. In the Command Window, type

 class(x)

followed by

 class(dim)

What is the result from each statement? Depending upon which one is the struct, you will have to modify the inputs accordingly.

[Massilon Toniolo da Silva]

Hi Geoff,

I have the same error and entered class(x) which resulted in x being the struct. Afterwards, I entered class(dim) and got undefined function or variable 'dim'. More precisely, which input should I modify and how should it be modified? Why the command class(dim) did not work? Could you please help me in matter? My Matlab skills are, unfortunately, very limited. Could you, therefore, explain a simple matter what went wrong? I would be very thankful for any help and guidance. Kind regards, Massilon

[Geoff Hayes]

Massilon - in the code provided by omid (see question), there was a variable called dim. If you have not defined this variable then you will get the error that you are observing.