STAT_Distribution.h

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#ifndef STAT_Distribution_H
#define STAT_Distribution_H

#include "STAT_Object.h"

#include "CORE_Array.h"

#include <boost/random/mersenne_twister.hpp>


DEFINE_SPTR(STAT_Distribution);
// boost::mt19937
// boost::ecuyer1988
// boost::minstd_rand
// boost::rand48
typedef boost::mt19937 RNGType;

class STAT_Distribution : public STAT_Object {
    SP_OBJECT(STAT_Distribution);
    // ATTRIBUTES

private:
    // Generator of pseudo number method
   
    static RNGType mRNGenerator;
    static tBoolean INIT_SEED;
  

private:
    
    
    // ASSOCIATIONS
    
    
protected: 
    // METHODS
  
    // CONSTRUCTORS 
  
    STAT_Distribution(void);
  
  
  
    // DESTRUCTORS 
  
  
    virtual ~STAT_Distribution(void);   
  
  
  
public:
    //----------------
    // NEW constructors
    // ---------------
    virtual SP::STAT_Distribution NewInstance() const=0;

    SP::STAT_Distribution NewCopyInstance() const {
        SP::STAT_Distribution dist=NewInstance();
        dist->copy(*this);
        return dist;
    };

    virtual void copy(const STAT_Distribution& d)=0;
    
    inline RNGType& getRNGenerator() {
        return mRNGenerator;
    };

    static void initSeed();
    
    static void initSeed(const long double& v);
    
    // -----------------------
    // USUAL Functions
    // ------------------------
    
    virtual tReal pdf(const tReal& x) const=0;
    
    virtual tReal cdf(const tReal& x) const=0;

    virtual tReal cdfc(const tReal& x) const=0;

    virtual tReal mean() const=0;

    virtual tReal variance() const=0;

    virtual tReal standardDeviation() const=0;

    virtual tReal random() const=0;
    
    virtual void computeSample(const int& n,CORE_RealArray& sample) const=0;
    
    virtual tReal computeGrowthRate() {
        return computeGrowthRate(0.5,false,0);
    };

    virtual tReal computeGrowthRate(const tReal& rho,const tReal& death) {
        return computeGrowthRate(0.5/(1-death),false,rho);
    };
    
    virtual tReal adjustGrowthRate(const tReal& rho,const tReal& death) {
        return computeGrowthRate(0.5/(1-death),true,rho);
    };
protected:
    /* \brief return the growth rate z of the distribution such that E(exp(-z.X))=v;
     * @param adjust: is true rescale the parameters of the distribution such as its growth rate is rho
     * 
     */
    virtual tReal computeGrowthRate(const tReal& v,
                                    const tBoolean& adjust,
                                    const tReal& rho) =0;
    
};

#endif