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

Hi,
I tried to used the linearize function of OpenModelica 1.9.0 beta4 with a simple thermal model composed of 3 thermal conductors and 2 heat capacitors, so called 3R2C model.
I want to obtain the symbolic state-space representation :
A,B,C,and D= f(C1,C2, G1,G2,G3)
where C1 is the parameter C value of the 1st heat capacitor, G1 the parameter G value of the 1st conductor...
However when I used the linearize function I get the A,B,C and D matrixes in a numerical form.
Is there some flags to set to get this true symbolic form (including the parameter "influences").
Regards,
Gilles