dont work syms??

nothing example with syms dont work in matlab for example this syms y(t) a eqn = diff(y,t,2) == a*y; ySol(t) = dsolve(eqn)

[John D'Errico]

The obvious questions: Do you have a license for the symbolic toolbox? Is that toolbox installed? What does

ver

tell you?

[thanos zisopoulos]

symbolic tolbox no write in ver..

[thanos zisopoulos]

syms y(t) a
eqn = diff(y,t,2) == a*y;
ySol(t) = dsolve(eqn)
Error using assignin
Invalid variable name "y(t)" in ASSIGNIN.

Error in syms (line 56)
      assignin('caller',varargin{i},sym(varargin{i}));

[Baojun Yuan]

same problem ...........

Answer 1

[Steven Lord]

Which release of MATLAB and Symbolic Math Toolbox are you using? Based on that error I suspect you're using a release prior to release R2012a, when the ability to create symbolic functions was introduced.

The functionality described in the online documentation is for the most recent release. If you're using a sufficiently older release (6+ years is "sufficiently older") I recommend referring to the documentation included in your installation. That local documentation will not refer to features introduced after the release you're using.