fuzzy logic example
#include <iostream>
#include <cmath>
#include <cstring>
const double cdMinimumPrice =0;
const double cdMaximumPrice =70;
using namespace std;
class CFuzzyFunction
{
protected :
double dLeft, dRight;
char cType;
char* sName;
public:
CFuzzyFunction(){};
virtual ~CFuzzyFunction(){ delete [] sName; sName=NULL;}
virtual void
setInterval(double l,
double r)
{dLeft=l; dRight=r;}
virtual void
setMiddle( double dL=0,
double dR=0)=0;
virtual void
setType(char c)
{ cType=c;}
virtual void
setName(const char* s)
{
sName = new char[strlen(s)+1];
strcpy(sName,s);
}
bool
isDotInInterval(double t)
{
if((t>=dLeft)&&(t<=dRight)) return true; else return false;
}
char getType(void)const{ return cType;}
void
getName() const
{
cout<<sName<<endl;
}
virtual double getValue(double t)=0;
};
class CTriangle : public CFuzzyFunction
{
private:
double dMiddle;
public:
void
setMiddle(double dL, double dR)
{
dMiddle=dL;
}
double
getValue(double t)
{
if(t<=dLeft)
return 0;
else if(t<dMiddle)
return (t-dLeft)/(dMiddle-dLeft);
else if(t==dMiddle)
return 1.0;
else if(t<dRight)
return (dRight-t)/(dRight-dMiddle);
else
return 0;
}
};
class CTrapezoid : public CFuzzyFunction
{
private:
double dLeftMiddle, dRightMiddle;
public:
void
setMiddle(double dL, double dR)
{
dLeftMiddle=dL; dRightMiddle=dR;
}
double
getValue(double t)
{
if(t<=dLeft)
return 0;
else if(t<dLeftMiddle)
return (t-dLeft)/(dLeftMiddle-dLeft);
else if(t<=dRightMiddle)
return 1.0;
else if(t<dRight)
return (dRight-t)/(dRight-dRightMiddle);
else
return 0;
}
};
int
main(void)
{
CFuzzyFunction *FuzzySet[3];
FuzzySet[0] = new CTrapezoid;
FuzzySet[1] = new CTriangle;
FuzzySet[2] = new CTrapezoid;
FuzzySet[0]->setInterval(-5,30);
FuzzySet[0]->setMiddle(0,20);
FuzzySet[0]->setType('r');
FuzzySet[0]->setName("low_price");
FuzzySet[1]->setInterval(25,45);
FuzzySet[1]->setMiddle(35,35);
FuzzySet[1]->setType('t');
FuzzySet[1]->setName("good_price");
FuzzySet[2]->setInterval(40,75);
FuzzySet[2]->setMiddle(50,70);
FuzzySet[2]->setType('r');
FuzzySet[2]->setName("to_expensive");
double dValue;
do
{
cout<<"\nImput the value->"; cin>>dValue;
if(dValue<cdMinimumPrice) continue;
if(dValue>cdMaximumPrice) continue;
for(int i=0; i<3; i++)
{
cout<<"\nThe dot="<<dValue<<endl;
if(FuzzySet[i]->isDotInInterval(dValue))
cout<<"In the interval";
else
cout<<"Not in the interval";
cout<<endl;
cout<<"The name of function is"<<endl;
FuzzySet[i]->getName();
cout<<"and the membership is=";
cout<<FuzzySet[i]->getValue(dValue);
}
}
while(true);
return EXIT_SUCCESS;
}