StructuredModel.cpp

Go to the documentation of this file.

/*
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 *
 * Written (W) 2012 Fernando José Iglesias García
 * Copyright (C) 2012 Fernando José Iglesias García
 */

#include <shogun/structure/StructuredModel.h>

using namespace shogun;

CStructuredModel::CStructuredModel() : CSGObject()
{
    init();
}

CStructuredModel::CStructuredModel(
        CFeatures*         features,
        CStructuredLabels* labels)
: CSGObject()
{
    init();

    m_features = features;
    m_labels   = labels;

    SG_REF(features);
    SG_REF(labels);
}

CStructuredModel::~CStructuredModel()
{
    SG_UNREF(m_labels);
    SG_UNREF(m_features);
}

void CStructuredModel::init_opt(
        SGMatrix< float64_t > & A,
        SGVector< float64_t > a,
        SGMatrix< float64_t > B,
        SGVector< float64_t > & b,
        SGVector< float64_t > lb,
        SGVector< float64_t > ub,
        SGMatrix< float64_t > & C)
{
    SG_ERROR("init_opt is not implemented for %s!\n", get_name());
}

void CStructuredModel::set_labels(CStructuredLabels* labels)
{
    SG_UNREF(m_labels);
    SG_REF(labels);
    m_labels = labels;
}

CStructuredLabels* CStructuredModel::get_labels()
{
    SG_REF(m_labels);
    return m_labels;
}

void CStructuredModel::set_features(CFeatures* features)
{
    SG_UNREF(m_features);
    SG_REF(features);
    m_features = features;
}

CFeatures* CStructuredModel::get_features()
{
    SG_REF(m_features);
    return m_features;
}

SGVector< float64_t > CStructuredModel::get_joint_feature_vector(
        int32_t feat_idx,
        int32_t lab_idx)
{
    CStructuredData* label = m_labels->get_label(lab_idx);
    SGVector< float64_t > ret = get_joint_feature_vector(feat_idx, label);
    SG_UNREF(label);

    return ret;
}

SGVector< float64_t > CStructuredModel::get_joint_feature_vector(
        int32_t feat_idx,
        CStructuredData* y)
{
    SG_ERROR("compute_joint_feature(int32_t, CStructuredData*) is not "
            "implemented for %s!\n", get_name());

    return SGVector< float64_t >();
}

float64_t CStructuredModel::delta_loss(int32_t ytrue_idx, CStructuredData* ypred)
{
    REQUIRE(ytrue_idx >= 0 || ytrue_idx < m_labels->get_num_labels(),
            "The label index must be inside [0, num_labels-1]\n");

    CStructuredData* ytrue = m_labels->get_label(ytrue_idx);
    float64_t ret = delta_loss(ytrue, ypred);
    SG_UNREF(ytrue);

    return ret;
}

float64_t CStructuredModel::delta_loss(CStructuredData* y1, CStructuredData* y2)
{
    SG_ERROR("delta_loss(CStructuredData*, CStructuredData*) is not "
            "implemented for %s!\n", get_name());

    return 0.0;
}

void CStructuredModel::init()
{
    SG_ADD((CSGObject**) &m_labels, "m_labels", "Structured labels",
            MS_NOT_AVAILABLE);
    SG_ADD((CSGObject**) &m_features, "m_features", "Feature vectors",
            MS_NOT_AVAILABLE);

    m_features = NULL;
    m_labels   = NULL;
}

bool CStructuredModel::check_training_setup() const
{
    // Nothing to do here
    return true;
}

int32_t CStructuredModel::get_num_aux() const
{
    return 0;
}

int32_t CStructuredModel::get_num_aux_con() const
{
    return 0;
}

float64_t CStructuredModel::risk(float64_t* subgrad, float64_t* W, TMultipleCPinfo* info)
{
    int32_t from=0, to=0;
    if (info)
    {
        from = info->_from;
        to = (info->N == 0) ? m_features->get_num_vectors() : from+info->N;
    }
    else
    {
        from = 0;
        to = m_features->get_num_vectors();
    }

    int32_t dim = this->get_dim();
    float64_t R = 0.0;
    for (int32_t i=0; i<dim; i++)
        subgrad[i] = 0;

    for (int32_t i=from; i<to; i++)
    {
        CResultSet* result = this->argmax(SGVector<float64_t>(W,dim,false), i, true);
        SGVector<float64_t> psi_pred = result->psi_pred;
        SGVector<float64_t> psi_truth = result->psi_truth;
        SGVector<float64_t>::vec1_plus_scalar_times_vec2(subgrad, 1.0, psi_pred.vector, dim);
        SGVector<float64_t>::vec1_plus_scalar_times_vec2(subgrad, -1.0, psi_truth.vector, dim);
        R += result->score;
        SG_UNREF(result);
    }

    return R;
}