action_on_galois_group.cpp

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/*
 * action_on_galois_group.cpp
 *
 *  Created on: Mar 23, 2019
 *      Author: betten
 */
 
 
 
#include "foundations/foundations.h"
#include "group_actions.h"
 
using namespace std;
 
 
namespace orbiter {
namespace layer3_group_actions {
namespace induced_actions {
 
 
action_on_galois_group::action_on_galois_group()
{
    null();
}
 
action_on_galois_group::~action_on_galois_group()
{
    free();
}
 
void action_on_galois_group::null()
{
    M = NULL;
}
 
void action_on_galois_group::free()
{
 
    null();
}
 
 
void action_on_galois_group::init(actions::action *A,
        int m, int verbose_level)
{
    int f_v = (verbose_level >= 1);
    ring_theory::longinteger_object go;
 
    if (f_v) {
        cout << "action_on_galois_group::init" << endl;
        cout << "m=" << m << endl;
        }
    action_on_galois_group::A = A;
    action_on_galois_group::m = m;
    if (A->type_G != matrix_group_t) {
        cout << "action_on_galois_group::init action "
                "not of matrix group type" << endl;
        exit(1);
        }
    M = A->G.matrix_grp;
    if (M->f_semilinear == FALSE) {
        cout << "action_on_galois_group::init "
                "M->f_semilinear == FALSE" << endl;
        exit(1);
    }
    q = M->GFq->q;
    degree = M->GFq->e;
    if (f_v) {
        cout << "degree=" << degree << endl;
        }
 
    if (f_v) {
        cout << "action_on_galois_group::init "
                "field order is " << q << endl;
        }
}
 
long int action_on_galois_group::compute_image(
        int *Elt, long int i, int verbose_level)
{
    //verbose_level = 1;
    int f_v = (verbose_level >= 1);
    long int a, b, j;
 
    if (f_v) {
        cout << "action_on_galois_group::compute_image "
                "i = " << i << endl;
        }
    if (i < 0 || i >= degree) {
        cout << "action_on_galois_group::compute_image "
                "i = " << i << " out of range" << endl;
        exit(1);
        }
 
    a = A->linear_entry_frobenius(Elt);
    b = i + a;
    j = b % degree;
 
    if (f_v) {
        cout << "action_on_galois_group::compute_image "
                "image of " << i << " is " << j << endl;
        }
    return j;
}
 
}}}