[GiNaC-list] Not factoring expression

[James Jackson]

Hi,

I've just started using GiNaC (and very nice it is too!), however I  
have some strange behavior with an expression not being simplified.  
One output of a linear equation solver is the expression:

(C_2 
*s 
^ 
2 
*L_2 
*V_1 
+ 
C_2 
*L_1 
*C_1 
*s 
^ 
4 
*L_2 
*V_1 
+ 
L_1 
*C_1 
*s 
^ 
2 
*V_1 
+ 
V_1 
)*(1 
+L_1*C_1*s^2+C_2*L_1*s^2+C_2*L_1*C_1*s^4*L_2+C_2*s^2*L_2)^(-1)*V_1^(-1)

What is happening is that the V_1 terms in the first bracket are not  
being factorised, and therefore no cancellation with the final  
(V_1)^(-1) term is occuring. All my symbols are created with a  
SymbolFactory pattern, so I can be sure each V_1 is the same object.

Can anyone suggest why GiNaC isn't simplifying this to cancel the V_1  
terms?

Regards,
James.