chi2.h

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#ifndef GUM_LEARNING_CHI2_H
#define GUM_LEARNING_CHI2_H
 
#include <agrum/agrum.h>
 
#include <agrum/base/core/hashTable.h>
 
#include <agrum/base/core/math/math_utils.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/base/core/math/chi2_inl.h>
#endif /* GUM_NO_INLINE */
 
#endif /* GUM_LEARNING_CHI2_H */