gammaLog2.h

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#ifndef GUM_GAMMA_LOG2_H
#define GUM_GAMMA_LOG2_H
 
#define USE_MATH_DEFINES_   // for Visual C++
 
#include <limits>
#include <vector>
 
#include <agrum/agrum.h>
 
#include <agrum/base/core/math/math_utils.h>
 
namespace gum {

  class GammaLog2 {
    public:
    // ============================================================================
    // ============================================================================

    explicit GammaLog2(bool requires_precision = false);

    GammaLog2(const GammaLog2& from);

    GammaLog2(GammaLog2&& from);

    ~GammaLog2();

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

    double operator()(double x) const;

    void setPrecision(bool p);

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

    double gammaLog2(double x) const;

 
    private:
    bool _requires_precision_{false};

    static constexpr double _inv_log2_{M_LOG2E};

    static constexpr double _log_sqrt_2pi_{GUM_LOG_SQRT_2PI};

    static const std::vector< double > _small_values_;
  };
 
} /* namespace gum */
 
#ifndef GUM_NO_INLINE
#  include <agrum/base/core/math/gammaLog2_inl.h>
#endif   // GUM_NO_INLINE
 
#endif   /* GUM_GAMMA_LOG2_H */