CrossValidationMulticlassStorage.cpp

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/*
 * 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.
 *
 * Copyright (C) 2012 Sergey Lisitsyn, Heiko Strathmann
 */

#include <shogun/evaluation/CrossValidationMulticlassStorage.h>
#include <shogun/evaluation/ROCEvaluation.h>
#include <shogun/evaluation/PRCEvaluation.h>
#include <shogun/evaluation/MulticlassAccuracy.h>

using namespace shogun;

CCrossValidationMulticlassStorage::CCrossValidationMulticlassStorage(bool compute_ROC, bool compute_PRC, bool compute_conf_matrices) :
    CCrossValidationOutput()
{
    m_initialized = false;
    m_compute_ROC = compute_ROC;
    m_compute_PRC = compute_PRC;
    m_compute_conf_matrices = compute_conf_matrices;
    m_pred_labels = NULL;
    m_true_labels = NULL;
    m_num_classes = 0;
    m_binary_evaluations = new CDynamicObjectArray();

    m_fold_ROC_graphs=NULL;
    m_conf_matrices=NULL;
}


CCrossValidationMulticlassStorage::~CCrossValidationMulticlassStorage()
{
    if (m_compute_ROC && m_fold_ROC_graphs)
    {
        SG_FREE(m_fold_ROC_graphs);
    }

    if (m_compute_PRC && m_fold_PRC_graphs)
    {
        SG_FREE(m_fold_PRC_graphs);
    }

    if (m_compute_conf_matrices && m_conf_matrices)
    {
        SG_FREE(m_conf_matrices);
    }

    if (m_binary_evaluations)
    {
        SG_UNREF(m_binary_evaluations);
    }
};


void CCrossValidationMulticlassStorage::post_init()
{
    if (m_initialized)
        SG_ERROR("CrossValidationMulticlassStorage was already initialized once\n")

    if (m_compute_ROC)
    {
        SG_DEBUG("Allocating %d ROC graphs\n", m_num_folds*m_num_runs*m_num_classes)
        m_fold_ROC_graphs = SG_MALLOC(SGMatrix<float64_t>, m_num_folds*m_num_runs*m_num_classes);
        for (int32_t i=0; i<m_num_folds*m_num_runs*m_num_classes; i++)
            new (&m_fold_ROC_graphs[i]) SGMatrix<float64_t>();
    }

    if (m_compute_PRC)
    {
        SG_DEBUG("Allocating %d PRC graphs\n", m_num_folds*m_num_runs*m_num_classes)
        m_fold_PRC_graphs = SG_MALLOC(SGMatrix<float64_t>, m_num_folds*m_num_runs*m_num_classes);
        for (int32_t i=0; i<m_num_folds*m_num_runs*m_num_classes; i++)
            new (&m_fold_PRC_graphs[i]) SGMatrix<float64_t>();
    }

    if (m_binary_evaluations->get_num_elements())
        m_evaluations_results = SGVector<float64_t>(m_num_folds*m_num_runs*m_num_classes*m_binary_evaluations->get_num_elements());

    m_accuracies = SGVector<float64_t>(m_num_folds*m_num_runs);

    if (m_compute_conf_matrices)
    {
        m_conf_matrices = SG_MALLOC(SGMatrix<int32_t>, m_num_folds*m_num_runs);
        for (int32_t i=0; i<m_num_folds*m_num_runs; i++)
            new (&m_conf_matrices[i]) SGMatrix<int32_t>();
    }

    m_initialized = true;
}

void CCrossValidationMulticlassStorage::init_expose_labels(CLabels* labels)
{
    ASSERT((CMulticlassLabels*)labels)
    m_num_classes = ((CMulticlassLabels*)labels)->get_num_classes();
}

void CCrossValidationMulticlassStorage::post_update_results()
{
    CROCEvaluation eval_ROC;
    CPRCEvaluation eval_PRC;
    int32_t n_evals = m_binary_evaluations->get_num_elements();
    for (int32_t c=0; c<m_num_classes; c++)
    {
        SG_DEBUG("Computing ROC for run %d fold %d class %d", m_current_run_index, m_current_fold_index, c)
        CBinaryLabels* pred_labels_binary = m_pred_labels->get_binary_for_class(c);
        CBinaryLabels* true_labels_binary = m_true_labels->get_binary_for_class(c);
        if (m_compute_ROC)
        {
            eval_ROC.evaluate(pred_labels_binary, true_labels_binary);
            m_fold_ROC_graphs[m_current_run_index*m_num_folds*m_num_classes+m_current_fold_index*m_num_classes+c] =
                eval_ROC.get_ROC();
        }
        if (m_compute_PRC)
        {
            eval_PRC.evaluate(pred_labels_binary, true_labels_binary);
            m_fold_PRC_graphs[m_current_run_index*m_num_folds*m_num_classes+m_current_fold_index*m_num_classes+c] =
                eval_PRC.get_PRC();
        }

        for (int32_t i=0; i<n_evals; i++)
        {
            CBinaryClassEvaluation* evaluator = (CBinaryClassEvaluation*)m_binary_evaluations->get_element_safe(i);
            m_evaluations_results[m_current_run_index*m_num_folds*m_num_classes*n_evals+m_current_fold_index*m_num_classes*n_evals+c*n_evals+i] =
                evaluator->evaluate(pred_labels_binary, true_labels_binary);
            SG_UNREF(evaluator);
        }

        SG_UNREF(pred_labels_binary);
        SG_UNREF(true_labels_binary);
    }
    CMulticlassAccuracy accuracy;

    m_accuracies[m_current_run_index*m_num_folds+m_current_fold_index] = accuracy.evaluate(m_pred_labels, m_true_labels);

    if (m_compute_conf_matrices)
    {
        m_conf_matrices[m_current_run_index*m_num_folds+m_current_fold_index] = CMulticlassAccuracy::get_confusion_matrix(m_pred_labels, m_true_labels);
    }
}

void CCrossValidationMulticlassStorage::update_test_result(CLabels* results, const char* prefix)
{
    m_pred_labels = (CMulticlassLabels*)results;
}

void CCrossValidationMulticlassStorage::update_test_true_result(CLabels* results, const char* prefix)
{
    m_true_labels = (CMulticlassLabels*)results;
}