Hello Gilles,

actually there is no flag to get the symbolic expressions,
since we are calculation the matrixes with an generic
directional derivative. Even more we don't differentiate
with respect to parameters.
But you can have a look at that directional derivative
with the debug flag: +d=dumpindxdae
Then you get for example for the VanDerPol model followinig
output:

Variables (2)

========================================

1:  $DER$Py$pDERA$PdummyVarA:STATE_DER()  type: Real 

2:  $DER$Px$pDERA$PdummyVarA:STATE_DER()  type: Real 





Equations (2, 2)

========================================

1/1 (1): $DER$Py$pDERA$PdummyVarA = lambda * (-2.0 * x$pDERA$Px * x * y + (1.0 - x ^ 2.0) * y$pDERA$Py) - x$pDERA$Px

2/2 (1): $DER$Px$pDERA$PdummyVarA = y$pDERA$Py

Where the equation represent directional derivative you can obtain
the columns of the Matrix A, by replacing the vector:
{ y$pDERA$Py, x$pDERA$Px}
by {1,0} and {0,1}.

I hope that helps a bit.
so long.
Willi

Hi Willi,
Thanks for the respond and sorry for the delay.

Actually I don't want to differentiate with respect to the parameters, I missspoke when I talk about parameters influences.
I want to differentiate with respect to the state variables, as it is done in the "linearize" function, but without the hard-coded parameter's value.
Therefore I want a form like A,B,C,and D= f(C1,C2, G1,G2,G3).

As you said I wil try to investigate the debug flag (dumpindxdae...).
Thanks again.
Regards,
Gilles