express.cpp

本人编写的数学表达式C++类,可以用来理解和表示数学表达式

// Function.cpp : Defines the class behaviors for the application.
//

#include "stdafx.h"
#include "math.h"
#include "express.h"
#include "resource.h"
#include <ctype.h>


#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif




IMPLEMENT_SERIAL(CExpression, CObject, 0)




//////////////////////////////////////////////////////////////////////
// CExpression Class
//////////////////////////////////////////////////////////////////////

//////////////////////////////////////////////////////////////////////
// Variabile Globale

//parametrii Global(50);




/////////////////////////////////////////////////////////////////////////////////
// Eliberarea memorie ocupate de arbore

void CExpression::elibmem ( arbore a)
{
if (a==NULL) return;
if (a->left!=NULL) elibmem(a->left);
if (a->right!=NULL) elibmem(a->right);
if (a->operatie == '`')
		delete a->valoarestr;
delete a;
}

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

CExpression::CExpression()
{
	m_Arbore = NULL;
	m_definitie = "";
	pozitie = 0;
	NumOfVar=0;
}

CExpression::~CExpression()
{
 elibmem (m_Arbore);
}

void CExpression::Serialize(CArchive & ar)
{
	if (ar.IsStoring())
	{
		// TODO: add storing code here
		ar << m_definitie;
	}
	else
	{
		// TODO: add loading code here
		ar >> m_definitie;
		m_Arbore = NULL;
		pozitie = 0;
		UpdateArbore();
		// After loading this object if it contains variables you should atach a variable 
		// Table to it
	}
}


int CExpression::UpdateArbore()
{
	if (m_definitie.IsEmpty())
		return 0;
	elibmem(m_Arbore); // Eliberarea memoriei ocupate de arbore
	m_Arbore = NULL;
	pozitie = 0;
	m_Arbore = expresie();
	SkipSpaces();
	if (m_definitie[pozitie]!='\0') 
	{
		elibmem(m_Arbore);
		m_Arbore = NULL;
	}

	if (m_Arbore == NULL)
		return pozitie;
	else return -1;
}

CExpression::arbore CExpression::expresie()
{
	arbore nod;
	arbore arb1 = termen();
	arbore arb2;
	if  (arb1 == NULL) return NULL;  // In caz de eroare terminate

	

	while ((m_definitie[pozitie]=='-') || (m_definitie[pozitie]=='+')) 
	{
		nod=new NOD;
		nod->left=arb1;
		nod->operatie=m_definitie[pozitie];
		pozitie++;
		arb2 = termen();
		nod->right=arb2;
		if  (arb2 == NULL) 
		{
			elibmem(nod);
			return NULL;  // In caz de eroare terminate
		}
		arb1 = nod;
	}
	return arb1;
}

CExpression::arbore CExpression::termen()
{
	arbore nod;
	arbore arb1 = putere();
	arbore arb2;
	if  (arb1 == NULL) return NULL;  // In caz de eroare terminate

	

	while ((m_definitie[pozitie]=='*') || (m_definitie[pozitie]=='/')) 
	{
		nod=new NOD;
		nod->left=arb1;
		nod->operatie=m_definitie[pozitie];
		pozitie++;
		arb2 = putere();
		nod->right=arb2;
		if  (arb2 == NULL) 
		{
			elibmem(nod);
			return NULL;  // In caz de eroare terminate
		}
		arb1 = nod;
	}
	return arb1;
}



CExpression::arbore CExpression::putere()
{
	arbore nod = NULL;
	arbore arb1 = logicalOp();
	arbore arb2;
	if  (arb1 == NULL) return NULL;  // In caz de eroare terminate

	

	while (m_definitie[pozitie]=='^') 
	{
		nod=new NOD;
		nod->left=arb1;
		nod->operatie=m_definitie[pozitie];
		pozitie++;
		arb2 = logicalOp();
		nod->right=arb2;
		if  (arb2 == NULL) 
		{
			elibmem(nod);
			return NULL;  // In caz de eroare terminate
		}
		arb1 = nod;
	}
	return arb1;
}


CExpression::arbore CExpression::factor()
{
 arbore nod = NULL,nod2 = NULL,left = NULL;
 while(m_definitie[pozitie] == ' ' && m_definitie[pozitie] != '\0')
	 pozitie++;

 if (m_definitie[pozitie]=='-')
   {
    nod = new NOD;
    left = new NOD;
    left->right=NULL;
    left->left=NULL;
    left->operatie='@';
    left->valoare=-1;
    nod->left=left;
    nod->operatie='*';
    pozitie++;
	nod->right = expresie();
	if (nod->right == NULL) return NULL;
	return nod;   
 }
 if (m_definitie[pozitie]=='(')
    {
      pozitie++;
      nod = expresie();
      if (nod == NULL) return NULL;
	  if (m_definitie[pozitie]!=')')
	  {
		elibmem(nod);
		return NULL;
	  }
	  pozitie++;
	  return nod;
    }
 else if (m_definitie[pozitie]=='|')
	 {
	   pozitie++;
	   nod2 = expresie();
	   if (nod2 == NULL) return NULL;
	   if (m_definitie[pozitie]!='|')
		{
			elibmem(nod);
			return NULL;
		}
	   nod = new NOD;
	   nod->left=nod2;
	   nod->right=NULL;
	   nod->operatie='|';
	   pozitie++;
	   return nod;
	}
     else return identificator();
 return nod;
}

CExpression::arbore CExpression::identificator()
{
	int poz;
	arbore nod = NULL,nod2 = NULL;
	arbore result = NULL;
	poz=pozitie;
	SkipSpaces();
	if (m_definitie[pozitie]=='\0') result  = NULL;
	if (isdigit(m_definitie[pozitie]))	// Is it a number?
	{
		BOOL digitf=TRUE;
		while  (digitf)
		{
			if((isdigit(m_definitie[pozitie]) || (m_definitie[pozitie]=='.')))
			{
				pozitie++;
				digitf=TRUE;
			}else if((m_definitie[pozitie]=='E')||(m_definitie[pozitie]=='e'))
			{
				pozitie++;
				digitf=TRUE;
				if((m_definitie[pozitie]=='+')||(m_definitie[pozitie]=='-')||(isdigit(m_definitie[pozitie])))
				{
					pozitie++;
				}
			}else
			{
				digitf=FALSE;
			}
		}
		nod = new NOD;
		nod->left = NULL; 
		nod->right = NULL;
		nod->operatie = '@';
		nod->valoare = atof(m_definitie.Mid(poz,pozitie-poz));
		result = nod;
	}
	if (isalpha(m_definitie[pozitie]))	// Am i an identifier ?
	{
		while  (isalnum(m_definitie[pozitie])) 
				pozitie++;

		CString id = m_definitie.Mid(poz,pozitie-poz);
		CString nid = id;
		id.MakeUpper();
		if (id =="SIN")		// Functia sinus CString
		{
			nod2 = factor();
			nod = new NOD;
			nod->left = nod2;
			nod->right=NULL;
			nod->operatie=F_SIN;
			SkipSpaces();
			return nod;
		}
		if (id =="COS")		// Functia sinus CString
		{
			nod2 = factor();
			nod = new NOD;
			nod->left = nod2;
			nod->right=NULL;
			nod->operatie=F_COS;
			SkipSpaces();
			return nod;
		}
		if (id =="EXP")		// Functia sinus CString
		{
			nod2 = factor();
			nod = new NOD;
			nod->left = nod2;
			nod->right=NULL;
			nod->operatie=F_EXP;
			SkipSpaces();
			return nod;
		}
		if (id =="SQRT")		// Functia sinus CString
		{
			nod2 = factor();
			nod = new NOD;
			nod->left = nod2;
			nod->right=NULL;
			nod->operatie=F_SQRT;
			SkipSpaces();
			return  nod;
		}
		if (id =="LOG")		// Functia sinus CString
		{
			nod2 = factor();
			nod = new NOD;
			nod->left = nod2;
			nod->right=NULL;
			nod->operatie=F_LOG;
			SkipSpaces();
			return nod;
		}
		if (id =="TG")		// Functia sinus CString
		{
			nod2 = factor();
			nod = new NOD;
			nod->left = nod2;
			nod->right=NULL;
			nod->operatie=F_TG;
			SkipSpaces();
			return nod;
		}
		if (id =="CTG")		// Functia sinus CString
		{
			nod2 = factor();
			nod = new NOD;
			nod->left = nod2;
			nod->right=NULL;
			nod->operatie=F_CTG;
			SkipSpaces();
			return nod;
		}
		if (id =="ASIN")		// Functia sinus CString
		{
			nod2 = factor();
			nod = new NOD;
			nod->left = nod2;
			nod->right=NULL;
			nod->operatie=F_ASIN;
			SkipSpaces();
			return nod;
		}
		if (id =="ACOS")		// Functia sinus CString
		{
			nod2 = factor();
			nod = new NOD;
			nod->left = nod2;
			nod->right=NULL;
			nod->operatie=F_ACOS;
			SkipSpaces();
			return nod;
		}
		if (id =="ATG")		// Functia sinus CString
		{
			nod2 = factor();
			nod = new NOD;
			nod->left = nod2;
			nod->right=NULL;
			nod->operatie=F_ATG;
			SkipSpaces();
			return nod;
		}
		if (id =="SINH")		// Functia sinus CString
		{
			nod2 = factor();
			nod = new NOD;
			nod->left = nod2;
			nod->right=NULL;
			nod->operatie=F_SINH;
			SkipSpaces();
			return nod;
		}
		if (id =="COSH")		// Functia sinus CString
		{
			nod2 = factor();
			nod = new NOD;
			nod->left = nod2;
			nod->right=NULL;
			nod->operatie=F_COSH;
			SkipSpaces();
			return nod;
		}
		if (id =="ASINH")		// Functia sinus CString
		{
			nod2 = factor();
			nod = new NOD;
			nod->left = nod2;
			nod->right=NULL;
			nod->operatie=F_ASINH;
			SkipSpaces();
			return nod;
		}
		if (id =="ACOSH")		// Functia sinus CString
		{
			nod2 = factor();
			nod = new NOD;
			nod->left = nod2;
			nod->right=NULL;
			nod->operatie=F_ACOSH;
			SkipSpaces();
			return nod;
		}
		if (id =="ABS")		// Functia sinus CString
		{
			nod2 = factor();
			nod = new NOD;
			nod->left = nod2;
			nod->right=NULL;
			nod->operatie=F_ABS;
			SkipSpaces();
			return nod;
		}
		if (id =="LOG10")		// Functia sinus CString
		{
			nod2 = factor();
			nod = new NOD;
			nod->left = nod2;
			nod->right=NULL;
			nod->operatie=F_LOG10;
			SkipSpaces();
			return nod;
		}
//		double* valuet=GetVarVal(nid);
//		if (valuet!=NULL)
		{
			nod = new NOD;
			nod -> left = NULL;
			nod -> right = NULL;
			nod -> operatie = '`';
			nod -> valoarestr = new CString(nid);
			result = nod;
		}
//		else 
//			result = NULL;
	}
	SkipSpaces();
	return result;
}

int CExpression::ChangeExpression(CString & expresie)
{
	m_definitie = expresie + '\0' + '\0';
	return UpdateArbore();
}


// Error code var
int code;


int CExpression::Value(double& valoare)
{
  code=0;
  if (m_Arbore == NULL) return -1;
  valoare=vexp(m_Arbore);
  return (code);
}


double CExpression::vexp ( arbore a )
{
double v;
if (a->operatie==NULL) {code=10;return 0;}
switch(a->operatie) 
 {
 case '+' : return( vexp(a->left)+vexp(a->right) );
 case '-' : return( vexp(a->left)-vexp(a->right) );
 case '*' : return( vexp(a->left)*vexp(a->right) );
 case '/' : v=vexp(a->right) ;
			 if (v==0)
			 {code=DIVISION_BY_0;return -vexp(a->left)/0.001;}
			 else
				return(vexp(a->left)/v);

 case F_SIN : return(sin(vexp(a->left)));
 case F_COS : return(cos(vexp(a->left)));
 case F_EXP : return(exp(vexp(a->left)));
 case F_SQRT : v=vexp(a->left) ;
			 if (v<0) {code=INVALID_DOMAIN;return 0;}
			 else return(sqrt(v));
 case F_LOG : v=vexp(a->left) ;
			 if (v<=0) {code=INVALID_DOMAIN;return 0;}
			 else return(log(v));
 case F_TG : return (tan (vexp(a->left)));
 case F_CTG : return (1 / tan (vexp(a->left)));
 case F_ASIN : return (asin (vexp(a->left)));
 case F_ACOS : return (acos (vexp(a->left)));
 case F_ATG : return (atan (vexp(a->left)));
 case F_SINH :
	 {
		 double x=(vexp(a->left));
		 return (exp(x)-exp(-x))/2.0;
	 }
 case F_COSH :
	 {
		 double x=(vexp(a->left));
		 return (exp(x)+exp(-x))/2.0;
	 }
 case F_ASINH :
	 {
		 double x=(vexp(a->left));
		 return (log(x+sqrt(x*x+1)));
	 }
 case F_ACOSH : 
	 {
		 double x=(vexp(a->left));
		 if(x>=1)
		 {
			 return (log(x+sqrt(x*x-1)));
		 }else
		 {
			 code=INVALID_DOMAIN;
			 return 0;
		 }
	 }
 case F_ABS : return (fabs(vexp(a->left)));
 case F_LOG10 : return (log10(vexp(a->left)));
 case '|' : return(fabs(vexp(a->left)));
 case '^' : return(pow(vexp(a->left),vexp(a->right)));
 case '@' : return (a->valoare);
 //logical operations evaluation
 case '<' : return( vexp(a->left)<vexp(a->right) );
 case '>' : return( vexp(a->left)>vexp(a->right) );
 case '!' : return(!vexp(a->right)) ;
 
 default  : {
				CString nid=*a->valoarestr;
				double* valuet=GetVarVal(nid);
				if (valuet==NULL) 
				{
					code=UNDEFINED_VARIABLE;
					return 0;
				}
				else 
				return *valuet;
			}
 }
}


CExpression::arbore CExpression::GetArbore()
{
	return m_Arbore;
}


CExpression::CExpression(CExpression & expresie)
{
	*this = expresie;
}




CExpression::arbore CExpression::CloneTree()
{
	return clone(m_Arbore);	
}


CExpression::arbore CExpression::clone(arbore arb)
{
	if (arb == NULL)
		return NULL;
	arbore clonArb = new NOD;
	*clonArb = *arb;
	clonArb->left = clone(arb->left);
	clonArb->right = clone(arb->right);
	return clonArb;
}

CExpression& CExpression::operator=(CExpression &expr)
{
	m_definitie = expr.m_definitie;
	pozitie = 0;
	m_Arbore = expr.CloneTree();
	return *this;
}

void CExpression::SkipSpaces()
{
	while ((m_definitie[pozitie]==' '||m_definitie[pozitie]==0x0a||m_definitie[pozitie]==0x0d) && m_definitie[pozitie]!='\0')
		pozitie ++;
}


///////////////////////////////////////////////////////////////////////
// the new inserted operations
// logical operations on the first level of priority
// warning: for operations with more than one character you nedd to modify sligthly the code
// See also the new inserted operations in the vexp function


CExpression::arbore CExpression::logicalOp()
{
	arbore nod;
	arbore arb1 = sgOp();
	arbore arb2;
	if  (arb1 == NULL) return NULL;  // In caz de eroare terminate

	while ((m_definitie[pozitie]=='<') || (m_definitie[pozitie]=='>') /* || another same priority operations*/) 
	{
		nod=new NOD;
		nod->left=arb1;
		nod->operatie=m_definitie[pozitie];
		pozitie++;
		arb2 = sgOp();
		nod->right=arb2;
		if  (arb2 == NULL) 
		{
			elibmem(nod);
			return NULL;  // In caz de eroare terminate
		}

		arb1 = nod;
	}
	return arb1;
}


CExpression::arbore CExpression::sgOp()
{
	arbore nod = NULL;
	arbore arb2;
	if ((m_definitie[pozitie]=='!') /* || another same priority operations*/) 
	{
		nod=new NOD;
		nod->left=NULL;
		nod->operatie=m_definitie[pozitie];
		pozitie++;
		arb2 = sgOp();
		nod->right=arb2;
		if  (arb2 == NULL) 
		{
			elibmem(nod);
			return NULL;  // In caz de eroare terminate
		}
	}
	else 
		nod = factor();
	return nod;
}
void CExpression::SetVarValue(CString* names, double* values, int num)
{
	VarNames=names;
	VarValues=values;
	NumOfVar=num;
}
double *CExpression::GetVarVal(CString & name)
{
	for(int i=0;i<NumOfVar;i++)
	{
		if(name==VarNames[i])
		{
			return (&VarValues[i]);
		}
	}
	return NULL;
}