Esempio n. 1
0
File: t-inv.c Progetto: goens/flint2
int
main(void)
{
    flint_rand_t state;
    long i;

    printf("inv....");
    fflush(stdout);

    flint_randinit(state);

    /* Test aliasing */
    for (i = 0; i < 400; i++)
    {
        fmpz_poly_mat_t A, Ainv;
        fmpz_poly_t den1, den2;
        long n, bits, deg;
        float density;
        int ns1, ns2;
        int result;

        n = n_randint(state, 8);
        deg = 1 + n_randint(state, 5);
        bits = 1 + n_randint(state, 100);
        density = n_randint(state, 100) * 0.01;

        fmpz_poly_mat_init(A, n, n);
        fmpz_poly_mat_init(Ainv, n, n);
        fmpz_poly_init(den1);
        fmpz_poly_init(den2);

        fmpz_poly_mat_randtest_sparse(A, state, deg, bits, density);

        ns1 = fmpz_poly_mat_inv(Ainv, den1, A);
        ns2 = fmpz_poly_mat_inv(A, den2, A);

        result = ns1 == ns2;

        if (result && ns1 != 0)
        {
            result = fmpz_poly_equal(den1, den2) &&
                fmpz_poly_mat_equal(A, Ainv);
        }

        if (!result)
        {
            printf("FAIL (aliasing)!\n");
            fmpz_poly_mat_print(A, "x"); printf("\n");
            fmpz_poly_mat_print(Ainv, "x"); printf("\n");
            abort();
        }

        fmpz_poly_mat_clear(A);
        fmpz_poly_mat_clear(Ainv);
        fmpz_poly_clear(den1);
        fmpz_poly_clear(den2);
    }

    /* Check A^(-1) = A = 1 */
    for (i = 0; i < 1000; i++)
    {
        fmpz_poly_mat_t A, Ainv, B, Iden;
        fmpz_poly_t den, det;
        long n, bits, deg;
        float density;
        int nonsingular;

        n = n_randint(state, 10);
        deg = 1 + n_randint(state, 5);
        bits = 1 + n_randint(state, 100);
        density = n_randint(state, 100) * 0.01;

        fmpz_poly_mat_init(A, n, n);
        fmpz_poly_mat_init(Ainv, n, n);
        fmpz_poly_mat_init(B, n, n);
        fmpz_poly_mat_init(Iden, n, n);
        fmpz_poly_init(den);
        fmpz_poly_init(det);

        fmpz_poly_mat_randtest_sparse(A, state, deg, bits, density);
        nonsingular = fmpz_poly_mat_inv(Ainv, den, A);
        fmpz_poly_mat_det_interpolate(det, A);

        if (n == 0)
        {
            if (nonsingular == 0 || !fmpz_poly_is_one(den))
            {
                printf("FAIL: expected empty matrix to pass\n");
                abort();
            }
        }
        else
        {
            if (!fmpz_poly_equal(den, det))
            {
                fmpz_poly_neg(det, det);
                printf("FAIL: den != det(A)\n");
                abort();
            }

            fmpz_poly_mat_mul(B, Ainv, A);
            fmpz_poly_mat_one(Iden);
            fmpz_poly_mat_scalar_mul_fmpz_poly(Iden, Iden, den);

            if (!fmpz_poly_mat_equal(B, Iden))
            {
                printf("FAIL:\n");
                printf("A:\n");
                fmpz_poly_mat_print(A, "x");
                printf("Ainv:\n");
                fmpz_poly_mat_print(Ainv, "x");
                printf("B:\n");
                fmpz_poly_mat_print(B, "x");
                printf("den:\n");
                fmpz_poly_print_pretty(den, "x");
                abort();
            }
        }

        fmpz_poly_clear(den);
        fmpz_poly_clear(det);
        fmpz_poly_mat_clear(A);
        fmpz_poly_mat_clear(Ainv);
        fmpz_poly_mat_clear(B);
        fmpz_poly_mat_clear(Iden);
    }

    flint_randclear(state);
    _fmpz_cleanup();
    printf("PASS\n");
    return 0;
}
Esempio n. 2
0
int
main(void)
{
    slong i;

    FLINT_TEST_INIT(state);

    flint_printf("nullspace....");
    fflush(stdout);

    

    for (i = 0; i < 200 * flint_test_multiplier(); i++)
    {
        fmpz_poly_mat_t A, N, AN;
        slong n, m, bits, deg, rank, nullity;
        float density;

        m = n_randint(state, 13);
        n = n_randint(state, 13);
        deg = 1 + n_randint(state, 5);
        bits = 1 + n_randint(state, 100);
        density = n_randint(state, 100) * 0.01;

        fmpz_poly_mat_init(A, m, n);
        fmpz_poly_mat_init(N, n, n);
        fmpz_poly_mat_init(AN, m, n);

        fmpz_poly_mat_randtest_sparse(A, state, deg, bits, density);

        rank = fmpz_poly_mat_rank(A);
        nullity = fmpz_poly_mat_nullspace(N, A);

        if (nullity + rank != n)
        {
            flint_printf("FAIL: wrong nullity!\n");
            flint_printf("rank = %wd\n", rank);
            flint_printf("nullity = %wd\n", nullity);
            fmpz_poly_mat_print(A, "x");
            flint_printf("\n");
            fmpz_poly_mat_print(N, "x");
            flint_printf("\n");
            abort();
        }

        if (fmpz_poly_mat_rank(N) != nullity)
        {
            flint_printf("FAIL: wrong rank(N) != nullity!\n");
            abort();
        }

        fmpz_poly_mat_mul(AN, A, N);

        if (!fmpz_poly_mat_is_zero(AN))
        {
            flint_printf("FAIL: A * N != 0\n");
            abort();
        }

        fmpz_poly_mat_clear(A);
        fmpz_poly_mat_clear(N);
        fmpz_poly_mat_clear(AN);
    }

    FLINT_TEST_CLEANUP(state);
    
    flint_printf("PASS\n");
    return 0;
}