chiSquare.h

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#ifndef GUM_CHI_SQUARE_H
#  define GUM_CHI_SQUARE_H
 
#  include <agrum/base/core/hashTable.h>
 
#  include <agrum/base/core/math/math_utils.h>
 
namespace gum {

 
  class ChiSquare {
    public:
    static double probaChi2(double x, Size df);
 
    private:

    static constexpr double _Z_MAX_ = 6.0;

    static constexpr double _CHI_EPSILON_ = 0.000001;

    static constexpr double _CHI_MAX_ = 99999.0;

    static constexpr double _LOG_SQRT_PI_ = 0.5723649429247000870717135;

    static constexpr double _I_SQRT_PI_ = 0.5641895835477562869480795;

    static constexpr double _BIGX_ = 20.0;

 

 
    static double _exp_(double x) { return (((x) < -_BIGX_) ? 0.0 : exp(x)); }
 
    static double _probaZValue_(double z);
  };
 
} /* namespace gum */
 
#endif   // GUM_CHI_SQUARE_H
 
 
// static HashTable<std::pair<double, unsigned long>, double>  _chi2Cache_;
// static HashTable<double, double>  _ZCache_;
// static Idx nbZ;
// static Idx nbChi;
// static Idx nbZt;
// static Idx nbChit;