chi2.h

Go to the documentation of this file.

/***************************************************************************
 *   Copyright (C) 2005 by Christophe GONZALES and Pierre-Henri WUILLEMIN  *
 *   {prenom.nom}_at_lip6.fr                                               *
 *                                                                         *
 *   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 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   This program is distributed in the hope that it will be useful,       *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
 *   GNU General Public License for more details.                          *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this program; if not, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/
#ifndef GUM_LEARNING_CHI2_H
#define GUM_LEARNING_CHI2_H

#include <agrum/agrum.h>
#include <agrum/core/math/math.h>
#include <agrum/core/hashTable.h>

#define GUM_LEARNING_CONFIDENCE_PROBA 0.05

namespace gum {

  // =========================================================================
  // ===                             CHI2 CLASS                            ===
  // =========================================================================

  class Chi2 {
    public:
    // ==========================================================================
    // ==========================================================================

    Chi2(const std::vector< std::size_t >& var_modalities,
         double confidence_proba = GUM_LEARNING_CONFIDENCE_PROBA);

    ~Chi2();

    // ==========================================================================
    // ==========================================================================

    void setConditioningNodes(const std::vector< Idx >& db_conditioning_ids);

    double criticalValue(const std::pair< Idx, Idx >& pair);

    double criticalValue(Idx var1, Idx var2);

    Size degreesOfFreedom(const std::pair< Idx, Idx >& pair);

    Size degreesOfFreedom(Idx var1, Idx var2);

    void setConfidenceProba(double new_proba);

    static double probaChi2(double x, Size df);

    private:
    const std::vector< std::size_t >& __modalities;

    double __confidence_proba;

    Size __conditioning_size;

    HashTable< Idx, double > __critical_values;

    static double __criticalValue(double proba, Size df);


    static double __probaZValue(double z);

    Chi2(const Chi2&) = delete;

    Chi2& operator=(const Chi2&) = delete;
  };

} /* namespace gum */

#ifndef GUM_NO_INLINE
#  include <agrum/core/math/chi2_inl.h>
#endif /* GUM_NO_INLINE */

#endif /* GUM_LEARNING_CHI2_H */