partial_derivative.cpp

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/*
 * partial_derivative.cpp
 *
 *  Created on: Mar 12, 2019
 *      Author: betten
 */
 
 
 
 
 
#include "foundations.h"
 
 
using namespace std;
 
 
namespace orbiter {
namespace layer1_foundations {
namespace ring_theory {
 
 
partial_derivative::partial_derivative()
{
    H = NULL;
    Hd = NULL;
    v = NULL;
    variable_idx = 0;
    mapping = NULL;
    null();
}
 
partial_derivative::~partial_derivative()
{
    freeself();
}
 
void partial_derivative::freeself()
{
    if (mapping) {
        FREE_int(mapping);
    }
    if (v) {
        FREE_int(v);
    }
    null();
}
 
void partial_derivative::null()
{
}
 
void partial_derivative::init(homogeneous_polynomial_domain *H,
        homogeneous_polynomial_domain *Hd,
        int variable_idx,
        int verbose_level)
{
    int f_v = (verbose_level >= 1);
    int i, j, c;
 
    if (f_v) {
        cout << "partial_derivative::init" << endl;
        }
    partial_derivative::H = H;
    partial_derivative::Hd = Hd;
    partial_derivative::variable_idx = variable_idx;
    v = NEW_int(H->get_nb_monomials());
    mapping = NEW_int(H->get_nb_monomials() * Hd->get_nb_monomials());
    Int_vec_zero(mapping, H->get_nb_monomials() * Hd->get_nb_monomials());
    if (Hd->degree != H->degree - 1) {
        cout << "partial_derivative::init Hd->degree != H->degree - 1" << endl;
        exit(1);
    }
    if (Hd->nb_variables != H->nb_variables) {
        cout << "partial_derivative::init Hd->nb_variables != H->nb_variables" << endl;
        exit(1);
    }
    if (Hd->q != H->q) {
        cout << "partial_derivative::init Hd->q != H->q" << endl;
        exit(1);
    }
    if (variable_idx >= H->nb_variables) {
        cout << "partial_derivative::init variable_idx >= H->nb_variables" << endl;
        exit(1);
    }
    for (i = 0; i < H->get_nb_monomials(); i++) {
        for (j = 0; j < H->nb_variables; j++) {
            v[j] = H->get_monomial(i, j);
        }
        //int_vec_copy(H->Monomials + i * H->nb_variables, H->v, H->nb_variables);
        if (v[variable_idx] == 0) {
            continue;
        }
        c = H->get_F()->Z_embedding(v[variable_idx]);
        v[variable_idx]--;
        j = Hd->index_of_monomial(v);
        mapping[i * Hd->get_nb_monomials() + j] = c;
    }
 
    if (f_v) {
        cout << "partial_derivative::init done" << endl;
        }
 
}
 
void partial_derivative::apply(int *eqn_in,
        int *eqn_out,
        int verbose_level)
{
    int f_v = (verbose_level >= 1);
 
    if (f_v) {
        cout << "partial_derivative::apply" << endl;
        }
 
    H->get_F()->Linear_algebra->mult_vector_from_the_left(eqn_in, mapping,
            eqn_out, H->get_nb_monomials(), Hd->get_nb_monomials());
 
    if (f_v) {
        cout << "partial_derivative::apply done" << endl;
        }
}
 
 
}}}