On Mon, 21 Feb 2000, Richard B. Kreckel wrote:
The other bug is with the fraction free elimination in ginac/matrix.cpp: If I try to solve the system [[ [[0,2-a]], [[5-4*a,3+2*a]] ]] * [[ [[x]], [[y]] ]] == [[ [[-2+5*a]], [[-5-2*a]] ]]
Looks like the reason is a problem in normal(): symbol a("a"); ex z=((-5-2*a)-((2-5*a)/(-2+a))*(3+2*a))/(5-4*a); cout << "z=" << z << endl; cout << "normal(z)=" << normal(z) << endl; z=(5-4*a)^(-1)*(-5-2*a-(3+2*a)*(2-5*a)*(-2+a)^(-1)) normal(z)=-(5-4*a)^(-1)*(-22+2*a*(-2+a)-10*a^2)*(-2+a)^(-1) -- Alexander Frink E-Mail: Alexander.Frink@Uni-Mainz.DE Institut fuer Physik Phone: +49-6131-3923391 Johannes-Gutenberg-Universitaet D-55099 Mainz, Germany