Hi,

I am try to test expressions with "match", but it not works 

always with the same expression. I think that the problem 

is at internal representation or at internal order. When 

I debug the code, same expression prints differ.

ex test = pow(log(x),2)/x;

cout << test; 

// sometimes x^(-1)*log(x)^2

// other sometimes log(x)^2*x^(-1)

How I can force GiNaC to unique representation?