|| || || || || ||

---

PrecisionAtN.h

Go to the documentation of this file.

#ifndef Impala_Core_Training_PrecisionAtN_h
#define Impala_Core_Training_PrecisionAtN_h

#include "Core/Training/Evaluation.h"
#include "Core/Table/Sort.h"
#include "Core/Table/Reverse.h"

namespace Impala
{
namespace Core
{
namespace Training
{


class PrecisionAtN : public Evaluation
{
public:

    PrecisionAtN(Table::AnnotationTable* annotation, int n) :
        Evaluation(annotation)
    {
        mN = n;
    }

    virtual double
    Compute(Table::ScoreTable* table)
    {
        Sort(table, 2, false);

        int positiveCount = 0;
        int i;
        for (i=0 ; i<table->Size() && i<mN ; ++i)
        {
            Quid q = table->Get1(i);
            if (mAnnotation->IsPositive(q))
                positiveCount++;
        }
        double precision = ((double)positiveCount)/((double)(i));
        return precision;
    }

private:

    int mN; // N is the number at which we compute the precision.

};

}//namespace Core
}//namespace Training
}//namespace Impala

#endif

---