Dear GAP forum, I have finite matrix groups, for example G:=Group([[0, 0, 0, 2, -1, 1, 1, -3], [0, 0, 0, -1, 1, 0, 0, 1], [0, 0, 0, 1, 0, 0, 0, -2], [0, 0, 0, 1, -1, 1, 1, -2], [0, 0, 0, 1, -1, 0, 1, -1], [0, 0, 1, 0, 0, 0, 0, -1], [0, 1, 0, 1, 0, 0, 0, -1], [1, -1, -1, 0, -1, 0, 0, -1]], [[-5, 0, 0, 2, 1, 4, 4, 4], [1, 0, 0, -1, 0, -1, 0, 0], [-2, 0, 0, 1, 0, 2, 1, 2], [-3, 0, 0, 1, 1, 3, 2, 2], [-2, 0, 0, 1, 0, 2, 2, 1], [-1, 0, 0, 0, 0, 1, 1, 1], [-2, 1, 1, 1, 1, 1, 1, 1], [-1, -1, 0, 0, 0, 1, 1, 1]]); I need to compute the conjugacy classes of elements of order 4 and/or with minimal polynomial x^2+1.
Of course I can do Filtered(ConjugacyClasses(G), g->Order(Representative(g))=4); or Filtered(ConjugacyClasses(G), g->Representative(g)^2=-IdentityMat(8)); but I have thousands of such groups so any suggestion to speed up the process is welcome. Maybe there is a way to compute only conjugacy classes of the right order ? Cheers, Bill. _______________________________________________ Forum mailing list Forum@gap-system.org https://mail.gap-system.org/mailman/listinfo/forum
