expDist.h

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#ifndef _expDist_h_
#define _expDist_h_
#include <random>

class ExpDist {

private:
    double maxInput;

    double unifRandom(double, double);

    std::mt19937_64 &generator;

public:
    
    // Constructor. maxDecimal is the maximum number less than 1,
    // using maximum digits in the double's mantissa, to use 
    // when sampling the dist. This prevents .999999... being 
    // turned into 1, causing a return of inf from the distribution
    //ExpDist(double maxDecimal, std::mt19937_64 &_generator);
    ExpDist(double maxDecimal,std::mt19937_64 &_generator);
    
    // Returns double using rv as "random variable"
    double getValue(double lambda, double rv);     
    
    // Generates its own random input to distribution
    double getValue(double lambda, double minInput, double maxInput);
        
    // Returns maximum value computer is able to produce
    // can be relatively small with certain parameters for lambda
    // due to precision issues. 
    double getMaxValue(double lambda);

    // Computes what the input value needs to be in 
    // order for the distribution to return "output" value
    double computeInput(double output, double lambda);
};

#endif