int acb_mat_solve(acb_mat_t X, const acb_mat_t A, const acb_mat_t B, slong prec) { int result; slong n, m, *perm; acb_mat_t LU; n = acb_mat_nrows(A); m = acb_mat_ncols(X); if (n == 0 || m == 0) return 1; perm = _perm_init(n); acb_mat_init(LU, n, n); result = acb_mat_lu(perm, LU, A, prec); if (result) acb_mat_solve_lu_precomp(X, perm, LU, B, prec); acb_mat_clear(LU); _perm_clear(perm); return result; }
int main() { slong iter; flint_rand_t state; flint_printf("lu...."); fflush(stdout); flint_randinit(state); for (iter = 0; iter < 10000; iter++) { fmpq_mat_t Q; acb_mat_t A, LU, P, L, U, T; slong i, j, n, qbits, prec, *perm; int q_invertible, r_invertible; n = n_randint(state, 8); qbits = 1 + n_randint(state, 100); prec = 2 + n_randint(state, 202); fmpq_mat_init(Q, n, n); acb_mat_init(A, n, n); acb_mat_init(LU, n, n); acb_mat_init(P, n, n); acb_mat_init(L, n, n); acb_mat_init(U, n, n); acb_mat_init(T, n, n); perm = _perm_init(n); fmpq_mat_randtest(Q, state, qbits); q_invertible = fmpq_mat_is_invertible(Q); if (!q_invertible) { acb_mat_set_fmpq_mat(A, Q, prec); r_invertible = acb_mat_lu(perm, LU, A, prec); if (r_invertible) { flint_printf("FAIL: matrix is singular over Q but not over R\n"); flint_printf("n = %wd, prec = %wd\n", n, prec); flint_printf("\n"); flint_printf("Q = \n"); fmpq_mat_print(Q); flint_printf("\n\n"); flint_printf("A = \n"); acb_mat_printd(A, 15); flint_printf("\n\n"); flint_printf("LU = \n"); acb_mat_printd(LU, 15); flint_printf("\n\n"); } } else { /* now this must converge */ while (1) { acb_mat_set_fmpq_mat(A, Q, prec); r_invertible = acb_mat_lu(perm, LU, A, prec); if (r_invertible) { break; } else { if (prec > 10000) { flint_printf("FAIL: failed to converge at 10000 bits\n"); abort(); } prec *= 2; } } acb_mat_one(L); for (i = 0; i < n; i++) for (j = 0; j < i; j++) acb_set(acb_mat_entry(L, i, j), acb_mat_entry(LU, i, j)); for (i = 0; i < n; i++) for (j = i; j < n; j++) acb_set(acb_mat_entry(U, i, j), acb_mat_entry(LU, i, j)); for (i = 0; i < n; i++) acb_one(acb_mat_entry(P, perm[i], i)); acb_mat_mul(T, P, L, prec); acb_mat_mul(T, T, U, prec); if (!acb_mat_contains_fmpq_mat(T, Q)) { flint_printf("FAIL (containment, iter = %wd)\n", iter); flint_printf("n = %wd, prec = %wd\n", n, prec); flint_printf("\n"); flint_printf("Q = \n"); fmpq_mat_print(Q); flint_printf("\n\n"); flint_printf("A = \n"); acb_mat_printd(A, 15); flint_printf("\n\n"); flint_printf("LU = \n"); acb_mat_printd(LU, 15); flint_printf("\n\n"); flint_printf("L = \n"); acb_mat_printd(L, 15); flint_printf("\n\n"); flint_printf("U = \n"); acb_mat_printd(U, 15); flint_printf("\n\n"); flint_printf("P*L*U = \n"); acb_mat_printd(T, 15); flint_printf("\n\n"); abort(); } } fmpq_mat_clear(Q); acb_mat_clear(A); acb_mat_clear(LU); acb_mat_clear(P); acb_mat_clear(L); acb_mat_clear(U); acb_mat_clear(T); _perm_clear(perm); } flint_randclear(state); flint_cleanup(); flint_printf("PASS\n"); return EXIT_SUCCESS; }