Undefined function or variable 'sym' error in MATLAB 2015b (GPTIPS)

Hello

Dear all experts

I am using a Toolbox written in MATLAB called GPTIPS (Genetic Programming Toolbox). I get an error of " Undefined function or variable 'sym' ". Since this toolbox is developed in 2014 or 2015 some of the features are not working with latest version of MATLAB (2016 and later on), so I installed the version 2015b which the toolbox feature is working. However, I get an error for 'sym' that is necessary for some calculations. I replaced 'sym' with 'syms' and I get another error of "Error using syms:Too many output arguments.". I also know that 'str2sym' will not work either, since it is provided for MATLAB version of 2017 and later.

Can anyone help me to get around with this sym error?

I should also say that I have the Symbolic Math Toolbox (version 9.3) installed.

Regards,

Answer 1

[Walter Roberson]

The Symbolic Mathematics Toolbox for R2015b was release 6.3.

It did have a function named sym, and syms was a slightly different function that was more a command.

Try

which -all sym

if it does not find anything then the toolbox is not installed properly. If it finds something but you still cannot invoke sym then you might possibly have a license issue.