How to specify initial conditions for a "Generic System" in the PDE App?

Dear Alan,

your answer given to my question unfortunately doesn't work...

First I've tried for u(t0) the expression

char('x.^2 + 5*cos(x.*y)','y')

and I got the error message

Then I tried as indicated in your link as an example for u'(t0) the expression

char('p(1,:).^2 + 5*cos(p(1,:).*p(2,:))','p(2,:)')

to get the nodal positions into play. But again I got an error message

So, I'm very helpless... I still does not understand, what is ment by " ...or a column vector of values on the nodes of the current mesh" and what is the MATLAB expression to achieve that!! Please help...

Thanks a lot, Anna

By the way: If I enter just constant numbers in the "char"-expressions, it's working...but I need the functions to apply the correct initial values at the nodes!