finite_field_implementation_wo_tables.cpp

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/*
 * finite_field_implementation_wo_tables.cpp
 *
 *  Created on: Sep 6, 2021
 *      Author: betten
 */
 
 
 
 
 
 
#include "foundations.h"
 
using namespace std;
 
 
 
namespace orbiter {
namespace layer1_foundations {
namespace field_theory {
 
 
 
finite_field_implementation_wo_tables::finite_field_implementation_wo_tables()
{
    F = NULL;
    v1 = v2 = v3 = NULL;
    GFp = NULL;
    FX = NULL;
    m = NULL;
    factor_polynomial_degree = 0;
    factor_polynomial_coefficients_negated = NULL;
    Fq = NULL;
    Alpha = NULL;
}
 
finite_field_implementation_wo_tables::~finite_field_implementation_wo_tables()
{
    if (v1) {
        FREE_int(v1);
    }
    if (v2) {
        FREE_int(v2);
    }
    if (v3) {
        FREE_int(v3);
    }
    if (factor_polynomial_coefficients_negated) {
        FREE_int(factor_polynomial_coefficients_negated);
    }
}
 
void finite_field_implementation_wo_tables::init(finite_field *F, int verbose_level)
{
    int f_v = (verbose_level >= 1);
 
    if (f_v) {
        cout << "finite_field_implementation_wo_tables::init" << endl;
    }
 
    finite_field_implementation_wo_tables::F = F;
 
 
    v1 = NEW_int(F->e);
    v2 = NEW_int(F->e);
    v3 = NEW_int(F->e);
 
 
    GFp = NEW_OBJECT(finite_field);
 
    if (f_v) {
        cout << "finite_field_implementation_wo_tables::init before GFp->finite_field_init" << endl;
    }
    GFp->finite_field_init(F->p, FALSE /* f_without_tables */, 0);
    if (f_v) {
        cout << "finite_field_implementation_wo_tables::init after GFp->finite_field_init" << endl;
    }
 
 
    FX = NEW_OBJECT(ring_theory::unipoly_domain);
 
 
    if (f_v) {
        cout << "finite_field_implementation_wo_tables::init before FX->create_object_by_rank_string" << endl;
    }
    FX->create_object_by_rank_string(m, F->my_poly, 0 /*verbose_level - 2*/);
    if (f_v) {
        cout << "finite_field_implementation_wo_tables::init m=";
        FX->print_object(m, cout);
        cout << endl;
    }
 
    Fq = NEW_OBJECT(ring_theory::unipoly_domain);
 
    if (f_v) {
        cout << "finite_field_implementation_wo_tables::init before Fq->init_factorring" << endl;
    }
    Fq->init_factorring(GFp, m, verbose_level - 1);
    if (f_v) {
        cout << "finite_field_implementation_wo_tables::init after Fq->init_factorring" << endl;
    }
 
    int i;
 
    factor_polynomial_degree = Fq->degree(m);
    factor_polynomial_coefficients_negated = NEW_int(factor_polynomial_degree + 1);
    for (i = 0; i <= factor_polynomial_degree; i++) {
        factor_polynomial_coefficients_negated[i] = F->negate(Fq->s_i(m, i));
    }
 
 
    if (f_v) {
        cout << "finite_field_implementation_wo_tables::init before Fq->create_object_by_rank" << endl;
    }
    Fq->create_object_by_rank(Alpha, F->alpha, __FILE__, __LINE__, 0 /*verbose_level - 2*/);
    if (f_v) {
        cout << "finite_field_implementation_wo_tables::init after Fq->create_object_by_rank" << endl;
    }
 
 
    if (f_v) {
        cout << "finite_field_implementation_wo_tables::init done" << endl;
    }
}
 
int finite_field_implementation_wo_tables::mult(int i, int j, int verbose_level)
{
    int f_v = (verbose_level >= 1);
 
    if (f_v) {
        cout << "finite_field_implementation_wo_tables::mult" << endl;
    }
 
    ring_theory::unipoly_object a, b, c;
    int k;
 
    Fq->create_object_by_rank(a, i, __FILE__, __LINE__, 0 /*verbose_level - 2*/);
    Fq->create_object_by_rank(b, j, __FILE__, __LINE__, 0 /*verbose_level - 2*/);
    Fq->create_object_of_degree_no_test(c, factor_polynomial_degree);
 
    if (f_v) {
        cout << "a=" << endl;
        Fq->print_object(a, cout);
        cout << endl;
        cout << "b=" << endl;
        Fq->print_object(b, cout);
        cout << endl;
        cout << "finite_field_implementation_wo_tables::mult before Fq->mult_mod_negated" << endl;
    }
 
    Fq->mult_mod_negated(a, b, c,
            factor_polynomial_degree,
            factor_polynomial_coefficients_negated,
            verbose_level);
 
    if (f_v) {
        cout << "finite_field_implementation_wo_tables::mult after Fq->mult_mod_negated" << endl;
    }
 
    k = Fq->rank(c);
    if (f_v) {
        cout << "c=" << endl;
        Fq->print_object(c, cout);
        cout << endl;
        cout << "i=" << i << ", j=" << j << " k=" << k << endl;
    }
 
    Fq->delete_object(a);
    Fq->delete_object(b);
    Fq->delete_object(c);
    if (f_v) {
        cout << "finite_field_implementation_wo_tables::mult done" << endl;
    }
    return k;
}
 
int finite_field_implementation_wo_tables::inverse(int i, int verbose_level)
{
    int f_v = (verbose_level >= 1);
 
    if (f_v) {
        cout << "finite_field_implementation_wo_tables::inverse" << endl;
    }
 
    ring_theory::unipoly_object a, u, v, g;
    int k;
 
    Fq->create_object_by_rank(a, i, __FILE__, __LINE__, 0 /*verbose_level - 2*/);
    Fq->create_object_of_degree_no_test(u, factor_polynomial_degree);
    Fq->create_object_of_degree_no_test(v, factor_polynomial_degree);
    Fq->create_object_of_degree_no_test(g, factor_polynomial_degree);
 
    if (f_v) {
        cout << "a=" << endl;
        Fq->print_object(a, cout);
        cout << endl;
        cout << "finite_field_implementation_wo_tables::inverse before Fq->extended_gcd" << endl;
    }
 
    Fq->extended_gcd(m, a, u, v, g, verbose_level);
 
    if (f_v) {
        cout << "finite_field_implementation_wo_tables::inverse after Fq->extended_gcd" << endl;
    }
 
    k = Fq->rank(v);
    if (f_v) {
        cout << "v=" << endl;
        Fq->print_object(v, cout);
        cout << endl;
        cout << "i=" << i << ", k=" << k << endl;
    }
 
    Fq->delete_object(a);
    Fq->delete_object(u);
    Fq->delete_object(v);
    Fq->delete_object(g);
    if (f_v) {
        cout << "finite_field_implementation_wo_tables::inverse done" << endl;
    }
    return k;
}
 
int finite_field_implementation_wo_tables::negate(int i, int verbose_level)
{
    int f_v = (verbose_level >= 1);
 
    if (f_v) {
        cout << "finite_field_implementation_wo_tables::negate" << endl;
    }
 
    geometry::geometry_global Gg;
 
    if (i < 0 || i >= F->q) {
        cout << "finite_field_implementation_wo_tables::negate out of range, i = " << i << endl;
        exit(1);
    }
    long int l, k;
 
    Gg.AG_element_unrank(F->p, v1, 1, F->e, i);
    for (l = 0; l < F->e; l++) {
        v2[l] = (F->p - v1[l]) % F->p;
    }
    k = Gg.AG_element_rank(F->p, v2, 1, F->e);
 
    if (f_v) {
        cout << "finite_field_implementation_wo_tables::negate done" << endl;
    }
    return k;
}
 
int finite_field_implementation_wo_tables::add(int i, int j, int verbose_level)
{
    int f_v = (verbose_level >= 1);
 
    if (f_v) {
        cout << "finite_field_implementation_wo_tables::add" << endl;
    }
 
    geometry::geometry_global Gg;
 
    if (i < 0 || i >= F->q) {
        cout << "finite_field_implementation_wo_tables::add out of range, i = " << i << endl;
        exit(1);
    }
    if (j < 0 || j >= F->q) {
        cout << "finite_field_implementation_wo_tables::add out of range, j = " << j << endl;
        exit(1);
    }
    long int l, k;
 
    Gg.AG_element_unrank(F->p, v1, 1, F->e, i);
    Gg.AG_element_unrank(F->p, v2, 1, F->e, j);
    for (l = 0; l < F->e; l++) {
        v3[l] = (v1[l] + v2[l]) % F->p;
    }
    k = Gg.AG_element_rank(F->p, v3, 1, F->e);
 
    if (f_v) {
        cout << "finite_field_implementation_wo_tables::add done" << endl;
    }
    return k;
}
 
 
 
}}}