Hello, Expanding an expression by calling the .expand() method is obsoleted by the now preferred method of the so-called "repeated reciprocal". You want to expand a*(a+b)? Here is how this is done nowadays. ex test = a*(a+b) ex expanded_test = 1/(1/test) Then again, maybe this was not the idea. A patch that is supposed to remove this feature from GiNaC is attached. Have a nice day, Chris