I've just updated my ubuntu to the latest long term support version, and when I ran the following script in wxmaxima it kept calculating forever when it reached the inversion of the matrix l. Ubuntu 14.04 comes with wxmaxima 13.04.2, I tried reinstalling it from the software center

l1:matrix([0,alpha_f*cf,alpha_s*cs*beta_y*sbx,alpha_s*cs*beta_z*sbx,alpha_s*a*beta_y/sqrt(rho),alpha_s*a*beta_z/sqrt(rho),alpha_f/rho]);

l7:matrix([0,alpha_f*cf,-alpha_s*cs*beta_y*sbx,alpha_s*cs*beta_z*sbx,alpha_s*a*beta_y/sqrt(rho),alpha_s*a*beta_z/sqrt(rho),alpha_f/rho]);

l3: matrix([0,-alpha_s*cs,-alpha_f*cf*beta_y*sbx,-alpha_f*cf*beta_z*sbx,-alpha_f*a*beta_y/sqrt(rho),-alpha_f*a*beta_z/sqrt(rho),alpha_s/rho]);

l5: matrix([0,alpha_s*cs,alpha_f*cf*beta_y*sbx,alpha_f*cf*beta_z*sbx,-alpha_f*a*beta_y/sqrt(rho),-alpha_f*a*beta_z/sqrt(rho),alpha_s/rho]);

l4:matrix([1, 0,0,0,0,0,-1/a^2]);

l6:matrix([0, 0,beta_z,-beta_y,-beta_z*sbx/sqrt(rho),beta_y*sbx/sqrt(rho),0]);

l2:matrix([0, 0,-beta_z,beta_y,-beta_z*sbx/sqrt(rho),beta_y*sbx/sqrt(rho),0]);

l: matrix(

[l1[1,1] ,l1[1,2], l1[1,3], l1[1,4],l1[1,5],l1[1,6],l1[1,7]],

[l2[1,1] ,l2[1,2], l2[1,3], l2[1,4],l2[1,5],l2[1,6],l2[1,7]],

[l3[1,1] ,l3[1,2], l3[1,3], l3[1,4],l3[1,5],l3[1,6],l3[1,7]],

[l4[1,1] ,l4[1,2], l4[1,3], l4[1,4],l4[1,5],l4[1,6],l4[1,7]],

[l5[1,1] ,l5[1,2], l5[1,3], l5[1,4],l5[1,5],l5[1,6],l5[1,7]],

[l6[1,1], l6[1,2], l6[1,3], l6[1,4],l6[1,5],l6[1,6],l6[1,7]],

[l7[1,1] ,l7[1,2], l7[1,3], l7[1,4],l7[1,5],l7[1,6],l7[1,7]]

);

r:ratsimp(invert(l));

I also tested this script in another computer with older versions of ubuntu and wxmaxima, and it worked well.

Does anyone know what happened? thanks!