Example #1
0
long
nmod_poly_mat_find_pivot_partial(const nmod_poly_mat_t mat,
                                    long start_row, long end_row, long c)
{
    long best_row, best_length, i;

    best_row = start_row;
    best_length = nmod_poly_length(nmod_poly_mat_entry(mat, start_row, c));

    for (i = start_row + 1; i < end_row; i++)
    {
        long l;

        l = nmod_poly_length(nmod_poly_mat_entry(mat, i, c));

        if (l != 0 && (best_length == 0 || l <= best_length))
        {
            best_row = i;
            best_length = l;
        }
    }

    if (best_length == 0)
        return -1;

    return best_row;
}
Example #2
0
long
nmod_poly_mat_max_length(const nmod_poly_mat_t A)
{
    long i, j, len, max;

    max = 0;

    for (i = 0; i < A->r; i++)
    {
        for (j = 0; j < A->c; j++)
        {
            len = nmod_poly_length(nmod_poly_mat_entry(A, i, j));
            max = FLINT_MAX(len, max);
        }
    }

    return max;
}
Example #3
0
int
main(void)
{
    int iter;
    FLINT_TEST_INIT(state);
    

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

    for (iter = 0; iter < 200 * flint_test_multiplier(); iter++)
    {
        nmod_poly_t poly, Q, R, t;
        mp_limb_t modulus;
        slong i, num_factors, exp, max_exp;
        int v, result;

        modulus = n_randtest_prime(state, 0);

        nmod_poly_init(poly, modulus);
        nmod_poly_init(t, modulus);
        nmod_poly_init(Q, modulus);
        nmod_poly_init(R, modulus);

        nmod_poly_set_coeff_ui(poly, 0, n_randint(state, modulus));
        num_factors = n_randint(state, 5);

        max_exp = 0;
        for (i = 0; i < num_factors; i++)
        {
            do {
                nmod_poly_randtest(t, state, n_randint(state, 10));
            } while (!nmod_poly_is_irreducible(t) ||
                    (nmod_poly_length(t) < 2));

            exp = n_randint(state, 4) + 1;
            if (n_randint(state, 2) == 0)
                exp = 1;

            nmod_poly_divrem(Q, R, poly, t);
            if (!nmod_poly_is_zero(R))
            {
                nmod_poly_pow(t, t, exp);
                nmod_poly_mul(poly, poly, t);
                max_exp = FLINT_MAX(exp, max_exp);
            }
        }

        v = nmod_poly_is_squarefree(poly);

        if (v == 1)
            result = (max_exp <= 1 && !nmod_poly_is_zero(poly));
        else
            result = (max_exp > 1 || nmod_poly_is_zero(poly));

        if (!result)
        {
            flint_printf("FAIL: %wu, %wd, %d\n", modulus, max_exp, v);
            nmod_poly_print(poly); flint_printf("\n");
            abort();
        }

        nmod_poly_clear(poly);
        nmod_poly_clear(t);
        nmod_poly_clear(Q);
        nmod_poly_clear(R);
    }

    FLINT_TEST_CLEANUP(state);
    
    flint_printf("PASS\n");
    return 0;
}
Example #4
0
int
main(void)
{
    int i;
    flint_rand_t state;

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

    flint_randinit(state);

    /* Test aliasing */
    for (i = 0; i < 2000; i++)
    {
        nmod_poly_t a, b;
        int square1, square2;
        mp_limb_t mod;
        mod = n_randtest_prime(state, 0);

        nmod_poly_init(a, mod);
        nmod_poly_init(b, mod);

        nmod_poly_randtest(a, state, 1 + n_randint(state, 50));

        if (n_randint(state, 2))
            nmod_poly_mul(a, a, a);

        square1 = nmod_poly_sqrt(b, a);
        square2 = nmod_poly_sqrt(a, a);

        if ((square1 != square2) || (square1 && !nmod_poly_equal(a, b)))
        {
            printf("FAIL: aliasing:\n");
            printf("square1 = %d, square2 = %d\n\n", square1, square2);
            printf("a: "); nmod_poly_print(a); printf("\n\n");
            printf("b: "); nmod_poly_print(b); printf("\n\n");
            abort();
        }

        nmod_poly_clear(a);
        nmod_poly_clear(b);
    }

    /* Test random squares */
    for (i = 0; i < 2000; i++)
    {
        nmod_poly_t a, b, c;
        int square;
        mp_limb_t mod;
        mod = n_randtest_prime(state, 0);

        nmod_poly_init(a, mod);
        nmod_poly_init(b, mod);
        nmod_poly_init(c, mod);

        nmod_poly_randtest(a, state, 1 + n_randint(state, 50));
        nmod_poly_mul(b, a, a);
        square = nmod_poly_sqrt(c, b);

        if (!square)
        {
            printf("FAIL: square reported nonsquare:\n");
            printf("a: "); nmod_poly_print(a); printf("\n\n");
            printf("b: "); nmod_poly_print(b); printf("\n\n");
            printf("c: "); nmod_poly_print(c); printf("\n\n");
            abort();
        }

        nmod_poly_mul(c, c, c);
        if (!nmod_poly_equal(c, b))
        {
            printf("FAIL: sqrt(b)^2 != b:\n");
            printf("a: "); nmod_poly_print(a); printf("\n\n");
            printf("b: "); nmod_poly_print(b); printf("\n\n");
            printf("c: "); nmod_poly_print(c); printf("\n\n");
            abort();
        }

        nmod_poly_clear(a);
        nmod_poly_clear(b);
        nmod_poly_clear(c);
    }

    /* Test "almost" squares */
    for (i = 0; i < 2000; i++)
    {
        nmod_poly_t a, b, c;
        long j;
        int square;
        mp_limb_t mod;
        mod = n_randtest_prime(state, 0);

        nmod_poly_init(a, mod);
        nmod_poly_init(b, mod);
        nmod_poly_init(c, mod);

        nmod_poly_randtest_not_zero(a, state, 1 + n_randint(state, 50));
        nmod_poly_mul(b, a, a);

        j = n_randint(state, nmod_poly_length(b));
        b->coeffs[j] = n_randint(state, mod);
        _nmod_poly_normalise(b);

        square = nmod_poly_sqrt(c, b);

        if (square)
        {
            nmod_poly_mul(c, c, c);
            if (!nmod_poly_equal(c, b))
            {
                printf("FAIL: sqrt(b)^2 != b:\n");
                printf("a: "); nmod_poly_print(a); printf("\n\n");
                printf("b: "); nmod_poly_print(b); printf("\n\n");
                printf("c: "); nmod_poly_print(c); printf("\n\n");
                abort();
            }
        }

        nmod_poly_clear(a);
        nmod_poly_clear(b);
        nmod_poly_clear(c);
    }

    flint_randclear(state);
    printf("PASS\n");
    return 0;
}
Example #5
0
int
main(void)
{
    int iter;
    FLINT_TEST_INIT(state);
    

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

    for (iter = 0; iter < 100 * flint_test_multiplier(); iter++)
    {
        nmod_poly_t poly1, poly2, poly3;
        mp_limb_t modulus;
        ulong infl1, infl, deflation;

        modulus = n_randtest_prime(state, 0);

        nmod_poly_init(poly1, modulus);
        nmod_poly_init(poly2, modulus);
        nmod_poly_init(poly3, modulus);

        nmod_poly_randtest(poly1, state, n_randint(state, 15));

        if (nmod_poly_length(poly1) <= 1)
        {
            if (nmod_poly_deflation(poly1) != nmod_poly_length(poly1))
            {
                flint_printf("FAIL: wrong deflation for constant polynomial\n");
                abort();
            }

            nmod_poly_deflate(poly2, poly1, n_randint(state, 5) + 1);
            if (!nmod_poly_equal(poly2, poly1))
            {
                flint_printf("FAIL: constant polynomial changed on deflation\n");
                abort();
            }
        }
        else
        {

            infl = n_randint(state, 13) + 1;
            infl1 = nmod_poly_deflation(poly1);

            nmod_poly_inflate(poly2, poly1, infl);

            deflation = nmod_poly_deflation(poly2);

            if (deflation != infl * infl1)
            {
                flint_printf("FAIL: deflation = %wu, inflation: %wu, %wu\n",
                    deflation, infl, infl1);
                flint_printf("poly1:\n"); nmod_poly_print(poly1); flint_printf("\n\n");
                flint_printf("poly2:\n"); nmod_poly_print(poly2); flint_printf("\n\n");
                abort();
            }

            nmod_poly_deflate(poly3, poly2, infl);
            if (!nmod_poly_equal(poly3, poly1))
            {
                flint_printf("FAIL: deflation = %wu, inflation: %wu, %wu\n",
                    deflation, infl, infl1);
                flint_printf("Deflated polynomial not equal to input:\n");
                flint_printf("poly1:\n"); nmod_poly_print(poly1); flint_printf("\n\n");
                flint_printf("poly2:\n"); nmod_poly_print(poly2); flint_printf("\n\n");
                flint_printf("poly3:\n"); nmod_poly_print(poly2); flint_printf("\n\n");
                abort();
            }

            nmod_poly_deflate(poly2, poly2, infl);
            if (!nmod_poly_equal(poly3, poly2))
            {
                flint_printf("FAIL: aliasing\n");
                abort();
            }
        }

        nmod_poly_clear(poly1);
        nmod_poly_clear(poly2);
        nmod_poly_clear(poly3);
    }

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