Error using SOSTOOLS, FINDLYAP() function

Hi,

I'm not sure how to fix this error. I tried using str2sym() function to create the variables instead of syms but I get the same error. I'm following the 2016 SOSTOOLS manual but using MATLAB 2019b with the latest SOSTOOLS github files.

>> syms x1 x2;
>> V = findlyap(f,[x1; x2],2)

Error using sym>convertChar (line 1548)
Character vectors and strings in the first argument can only specify a variable or number. To evaluate character vectors and strings representing symbolic
expressions, use 'str2sym'.

Error in sym>tomupad (line 1255)
        S = convertChar(x);

Error in sym (line 222)
                S.s = tomupad(x);

Error in mysympower (line 58)
ZTemp = sym(ZTemp);

Error in findlyap (line 96)
       expr1 = expr1 - epsmat(i,:) * mysympower(vars(i),[2:2:degree]');

Thanks,

Matt

[Yi ling]

Hello! Sorry I come late. You can download the newest version of SOSTOOLS, which is SOSTOOLS.304.zip here.

http://www.cds.caltech.edu/sostools/

But I cannot ensure that this will help you. Just try it. I have tried and the problem is solved.