BCCauchyPrior.h

#ifndef __BCCAUCHYPRIOR__H
#define __BCCAUCHYPRIOR__H

/*
 * Copyright (C) 2007-2018, the BAT core developer team
 * All rights reserved.
 *
 * For the licensing terms see doc/COPYING.
 * For documentation see http://mpp.mpg.de/bat
 */

// ---------------------------------------------------------

#include "BCPrior.h"

#include <limits>

class TF1;

// ---------------------------------------------------------

class BCCauchyPrior : public BCPrior
{
public:
    BCCauchyPrior(double mean, double scale);

    virtual ~BCCauchyPrior() {};

    virtual BCPrior* Clone() const
    { return new BCCauchyPrior(*this); }

    virtual bool IsValid() const
    { return std::isfinite(fMean) and std::isfinite(fScale) and fScale > 0;}

    virtual double GetLogPrior(double x)
    { return log(fScale) - log(fScale * fScale + (x - fMean) * (x - fMean)) - log(M_PI); }

    virtual double GetMode(double xmin = -std::numeric_limits<double>::infinity(), double xmax = std::numeric_limits<double>::infinity())
    { if (fMean < xmin) return xmin; if (fMean > xmax) return xmax; return fMean; }

    virtual double GetRawMoment(unsigned n, double xmin = -std::numeric_limits<double>::infinity(), double xmax = std::numeric_limits<double>::infinity());

    virtual double GetIntegral(double xmin = -std::numeric_limits<double>::infinity(), double xmax = std::numeric_limits<double>::infinity());

    virtual double GetScale() const
    { return fScale; }

    virtual void SetMean(double mean)
    { fMean = mean; }

    virtual void SetScale(double scale)
    { fScale = scale; }

    virtual void SetParameters(double mean, double scale)
    { SetMean(mean); SetScale(scale); }

protected:
    double fMean;                            
    double fScale;                       
};

#endif