mathexpr: Introduce changes by Jean-Philippe Meuret

mathexpr/mathexpr/mathexpr.cpp

@@ -1,6 +1,6 @@
 /*
 
-mathexpr.cpp version 2.0
+mathexpr.cpp version 2.1
 
 Copyright (c) 1997-2000 Yann OLLIVIER
 
@@ -12,7 +12,33 @@ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLI
 
 */
 
-#include"mathexpr.h"
+/* 2009 changes by Jean-Philippe Meuret <jpmeuret@free.fr> for Qatsh
+   - added EFunction class to support external functions with any number of parameters
+   - fixed memory leaks in ROperation::Expr() in the Num, Var and Error cases
+   - added code comments in several places
+   - ROperation::ROperation(const char*,int,PRVar*,int,PRFunction*) :
+     changed 1st arg from 'char*' to 'const char*' for GCC 4.2 (deprecated conversion)
+   - optimised IsNumeric(char), IsFunction(const char*,int,int,PRFunction*),
+     and IsolateVars(...).
+   - added parenthesis at line 513 on GCC suggestion :
+     before: if(s[i]==opc&&(op!=Sub||i&&s[i-1]==')'))return i;
+     after : if(s[i]==opc&&(op!=Sub||(i&&s[i-1]==')')))return i;
+
+   TODO:
+   - make code more readable (1 instruction per line, consistent indentation,
+     at least all the end-of-block '}' on their own line, ...)
+   - give member data a special name, for easier understanding (ex: a leading "_" or "m_")
+   - reimplement code parts without any goto instruction
+   - add more comments
+   - use constants everywhere the same litteral is used more than once in the code
+   - use strxxx standard libC functions for all string manipulations
+   - and even better ... move all "[const] char*" to sdt::string
+ */
+
+#include <stdarg.h>
+
+#include "mathexpr.h"
+
 
 char* MidStr(const char*s,int i1,int i2)
 {
@@ -27,10 +53,12 @@ char* MidStr(const char*s,int i1,int i2)
  s1[i2-i1+1]=0;return s1;
 }
 
+// Return a copy of the given string (use strdup ?)
 char* CopyStr(const char*s)
 {char*s1=new char[strlen(s)+1];char*s12=s1;const char*s2=s;
 while((*s12++=*s2++));return s1;}
 
+// Insert a char at a given position in a string (increase string length by 1)
 void InsStr(char*&s,int n,char c)// Warning : deletes the old string
 {if(n<0||n>(int)strlen(s))return;
 char*s1=new char[strlen(s)+2];
@@ -48,6 +76,7 @@ for(i=0;s[i];i++)if(s[i]!=s2[i])return 0;
 return 1;
 }
 
+// Tell if s[n...] == s2
 signed char CompStr(const char*s,int n,const char*s2)
 {if(n<0||n>=(int)strlen(s)||n+(int)strlen(s2)>(int)strlen(s))return 0;
 int i;
@@ -72,7 +101,49 @@ RVar::RVar(const char*namep,double*pvalp)
 {pval=pvalp;name=CopyStr(namep);}
 
 RVar::~RVar()
-{if(name!=NULL)delete[] name;}
+{
+  if(name!=NULL)delete[] name;
+}
+
+EFunction::EFunction(unsigned nvarsp)
+{
+  nvars = nvarsp;
+  pvars = new double[nvarsp];
+}
+
+EFunction::~EFunction()
+{
+  if (pvars)
+    delete[] pvars;
+}
+
+double EFunction::operator()(double* pvarsp)
+{
+  // Store variables in the pvars array.
+  unsigned i;
+  for (i = 0; i < nvars; i++)
+    pvars[i] = pvarsp[i];
+
+  // Compute value.
+  return Val();
+}
+
+double EFunction::operator()(double var1p, ...)
+{
+  // Store 1st variable (always here) in the pvars array.
+  pvars[0] = var1p;
+
+  // Store other variables in the pvars array.
+  va_list vl;
+  va_start(vl, var1p);
+  unsigned i;
+  for (i = 1; i < nvars; i++)
+	pvars[i] = (double)va_arg(vl, double);
+  va_end(vl);
+
+  // Compute value.
+  return Val();
+}
 
 RFunction::RFunction()
 {
@@ -86,11 +157,18 @@ RFunction::RFunction(double ((*pfuncvalp)(double)))
   nvars=1;ppvar=NULL;op=ErrVal;buf=NULL;
 }
 
+RFunction::RFunction(EFunction& efunc)
+{
+  type=2;pfuncobjval=&efunc;name=new char[1];name[0]=0;
+  nvars=efunc.nvars;ppvar=NULL;op=ErrVal;buf=NULL;
+}
+
 RFunction::RFunction(const RFunction& rfunc)
 {
   if(this==&rfunc)return;
   type=rfunc.type;op=rfunc.op;
   pfuncval=rfunc.pfuncval;
+  pfuncobjval=rfunc.pfuncobjval;
   name=CopyStr(rfunc.name);
   nvars=rfunc.nvars;
   if(rfunc.ppvar!=NULL&&nvars){
@@ -129,6 +207,7 @@ RFunction& RFunction::operator=(const RFunction& rfunc)
   if(this==&rfunc)return *this;
   type=rfunc.type;op=rfunc.op;
   pfuncval=rfunc.pfuncval;
+  pfuncobjval=rfunc.pfuncobjval;
   delete[]name;
   name=CopyStr(rfunc.name);
   if(ppvar!=NULL)delete[]ppvar;
@@ -150,6 +229,7 @@ double RFunction::Val(double x) const
 {
   if(type==-1||nvars>=2)return ErrVal;
   if(type==0)return (*pfuncval)(x);
+  if(type==2)return (*pfuncobjval)(x);
   double xb=*(*ppvar)->pval,y;
   *(*ppvar)->pval=x;  // Warning : could cause trouble if this value is used in a parallel process
   y=op.Val();
@@ -161,6 +241,7 @@ double RFunction::Val(double*pv) const
 {
   if(type==-1)return ErrVal;
   if(type==0)return (*pfuncval)(*pv);
+  if(type==2)return (*pfuncobjval)(pv);
   double y;
   int i;
   for(i=0;i<nvars;i++){
@@ -344,8 +425,8 @@ ROperation ApplyOperator(int n,ROperation**pops,ROperation (*func)(const ROperat
 
 ROperation RFunction::operator()(const ROperation& op)
 {
-  /* Code to use to replace explcitly instead of using a pointer to
+  /* Code to use to replace explicitly instead of using a pointer to
-     if(nvars!=op.NMembers()||type==-1||type==0)return ErrVal;
+     if(nvars!=op.NMembers()||type==-1||type==0||type==2)return ErrVal;
      ROperation op2=*pop;int i;
      RVar**ppvar2=new PRVar[nvars];char s[11]="";
      for(i=0;i<nvars;i++){
@@ -364,24 +445,29 @@ ROperation RFunction::operator()(const ROperation& op)
   return op2;
 }
 
-//Auxiliary string functions
+//Auxiliary string functions=====================================================
 
-void SupprSpaces(char*&s)//Deletes the old string
+// Remove spaces, tabs and line feeds (deletes the old string)
+void SupprSpaces(char*&s)
 {
  int i;
  for(i=0;s[i];i++)if(s[i]==' '||s[i]=='\t'||s[i]=='\n')DelStr(s,i--);
 }
 
+// Tell if a char is part of a decimal literal (decimal digits and decimal dot).
 signed char IsNumeric(char c)
-{if(c!='0'&&c!='1'&&c!='2'&&c!='3'&&c!='4'
+{
-	&&c!='5'&&c!='6'&&c!='7'&&c!='8'&&c!='9'&&c!='.')return 0;
+  if((c<'0'||c>'9')&&c!='.')
-return 1;
+    return 0;
+  return 1;
 }
 
+// Tell if a string is a decimal literal (TODO: fix positive answer even when multiple dots).
 signed char IsTNumeric(char *s)
 {int i;for(i=0;i<(int)strlen(s);i++)if(!IsNumeric(s[i]))return 0;return 1;
 }
 
+//Searchs the corresponding bracket of an opening bracket
 int SearchCorOpenbracket(char*s,int n)  //Searchs the corresponding bracket of an opening bracket
 {if(n>=(int)strlen(s)-1)return -1;
 int i,c=1;
@@ -392,6 +478,7 @@ for(i=n+1;s[i];i++){
 return -1;
 }
 
+//Searchs the corresponding bracket of a closing bracket
 int SearchCorClosebracket(char*s,int n)  //Searchs the corresponding bracket of a closing bracket
 {if(n<1)return -1;
 int i,c=1;
@@ -419,17 +506,21 @@ int SearchOperator(char*s,ROperator op)
   };
   int i;
   for(i=(int)strlen(s)-1;i>=0;i--){
-    if(s[i]==opc&&(op!=Sub||i&&s[i-1]==')'))return i;
+    if(s[i]==opc&&(op!=Sub||(i&&s[i-1]==')')))return i;
     if(s[i]==')'){i=SearchCorClosebracket(s,i);if(i==-1)return -1;};
   };
   return -1;
 }
 
 void SimplifyStr(char*&s) //Warning : deletes the old string
-{if(!strlen(s))return;
+{
+  // Nothing more to do if string is empty
+if(!strlen(s))return;
+  // Remove useless matching parenthesis (1st and last char)
 char*s1=s,*s2=s+strlen(s);signed char ind=0;
 if(s1[0]=='('&&SearchCorOpenbracket(s1,0)==s2-s1-1){
 	s1++;s2--;ind=1;}
+  // Return an empty string if nothing remains
 if(s1==s2)
 {
 	delete[]s;
@@ -437,7 +528,9 @@ if(s1==s2)
 	s[0]=0;
 	return;
 }
+  // Remove any leading spaces
 if(s1[0]==' '){ind=1;while(s1[0]==' '&&s1<s2)s1++;}
+  // Return an empty string if nothing remains
 if(s1==s2)
 {
 	delete[]s;
@@ -445,14 +538,19 @@ if(s1==s2)
 	s[0]=0;
 	return;
 }
+  // Remove any ending spaces
 if(*(s2-1)==' '){ind=1;while(s2>s1&&*(s2-1)==' ')s2--;}
 *s2=0;
+  // Replace input string by simplified one
 s1=CopyStr(s1);delete[]s;s=s1;
+  // Continue simplification (recursive) if needed
 if(ind)SimplifyStr(s);
 }
 
 int max(int a, int b){return (a>b?a:b);}
 
+// Detect the name of a variable from the given list, and return its length ;
+// the longest possible name is kept (xyz wins against xy)
 int IsVar(const char*s,int n,int nvar,PRVar*ppvar)
 {
   if(n<0||n>(int)strlen(s))return 0;
@@ -461,6 +559,7 @@ int IsVar(const char*s,int n,int nvar,PRVar*ppvar)
   return l;
 }
 
+// Detect the name of a standard function, and return its length
 int IsFunction(const char*s,int n)
 {
   if(CompStr(s,n,"sin")||CompStr(s,n,"cos")||CompStr(s,n,"exp")
@@ -474,15 +573,17 @@ int IsFunction(const char*s,int n)
   return 0;
 }
 
+// Detect the name of a function (be it a user defined one from the given list, or a standard one),
+// and return its length ; the longest possible name is kept (xyz wins against xy)
+// Limitations: standard functions are searched first, and may mask user defined ones
+// whose name begins with a standard one (ex: user "sine" masked by standard "sin")
+// WARNING: IF PATCHED TO DO OTHERWISE, SHOULD BE PATCHED TOGETHER WITH THE
+//          PARSER BELOW which treats standard functions before user-defined ones
 int IsFunction(const char*s,int n,int nfunc,PRFunction*ppfunc)
-	//Not recognized if a user-defined function is eg "sine" ie begins like
-	//a standard function
-	//IF PATCHED TO DO OTHERWISE, SHOULD BE PATCHED TOGETHER WITH THE
-	//PARSER BELOW which treats standard functions before user-defined ones
 {
   int l=IsFunction(s,n);
   if(l)return l;
-  int i;l=0;
+  int i;
   for(i=0;i<nfunc;i++)if(CompStr(s,n,ppfunc[i]->name))l=max(l,strlen(ppfunc[i]->name));
   return l;
 }
@@ -492,49 +593,68 @@ signed char IsFunction(ROperator op)
 	op==Atan||op==Asin||op==Acos||op==Atan||op==Sqrt||op==Opp);
 }
 
+// Enclose numbers between parenthesis (deletes the old string).
 void IsolateVars(char*&s,int nvar,PRVar*ppvar,int nfunc,PRFunction*ppfunc)//Deletes the old string
 {
   int i,j;
   i=0;
   for(i=0;s[i];i++){
+    // Jump over a (...) bloc if any
     if(s[i]=='('){i=SearchCorOpenbracket(s,i);if(i==-1)return;continue;};
+    // When detecting a variable or constant name, if no longer function name can match,
+    // and if enclose it between ( and )
     if(((j=IsVar(s,i,nvar,ppvar))>IsFunction(s,i,nfunc,ppfunc))||((CompStr(s,i,"pi")||CompStr(s,i,"PI")||CompStr(s,i,"Pi"))&&(j=2))){
       InsStr(s,i,'(');InsStr(s,i+j+1,')');i+=j+1;continue;};
-    if(IsFunction(s,i,nfunc,ppfunc)){i+=IsFunction(s,i,nfunc,ppfunc)-1;if(!s[i])return;continue;};
+    if((j=IsFunction(s,i,nfunc,ppfunc))){i+=j-1;if(!s[i])return;continue;};
   };
 }
 
+// Enclose numbers between parenthesis (deletes the old string).
 void IsolateNumbers(char*&s,int nvar,RVar**ppvar,int nfunc,RFunction**ppfunc)//Deletes the old string
 {
-  int i,i2,ind=0,t1,t2;
+  int i,i2=0,ind=0,t1,t2;
   for(i=0;s[i];i++){
+    // When detecting the end of a number, enclose it between ( and )
     if(ind&&!IsNumeric(s[i])){ind=0;InsStr(s,i2,'(');i++;InsStr(s,i,')');continue;};
+    // Jump over a variable or a function name if any
 		t1=IsVar(s,i,nvar,ppvar);t2=IsFunction(s,i,nfunc,ppfunc);
     if(t1||t2){i+=max(t1,t2)-1;continue;};
+    // Jump over a (...) bloc if any (the remainder of the function "call")
     if(s[i]=='('){i=SearchCorOpenbracket(s,i);if(i==-1)return;continue;};
+    // Here, we detect the beginning of a number
     if(!ind&&IsNumeric(s[i])){i2=i;ind=1;};
   };
+  // If the end of a number has not yet been detected, now it _is_, so enclose it between ( and )
 if(ind)InsStr(s,i2,'(');i++;InsStr(s,i,')');
 }
 
-ROperation::ROperation(char*sp,int nvar,PRVar*ppvarp,int nfuncp,PRFunction*ppfuncp)
+ROperation::ROperation(const char*sp,int nvar,PRVar*ppvarp,int nfuncp,PRFunction*ppfuncp)
 {
   ValC=ErrVal;mmb1=NULL;mmb2=NULL;pvar=NULL;op=ErrOp;pvarval=NULL;containfuncflag=0;pfunc=NULL;pinstr=NULL;pvals=NULL;ppile=NULL;pfuncpile=NULL;
   int i,j,k,l;signed char flag=1;
   char*s=CopyStr(sp),*s1=NULL,*s2=NULL;
+  // Simplify formula and remove leading : and ; (why ?)
   SimplifyStr(s);if(!s[0]||!strcmp(s,"Error")){goto fin;}
   while(s[0]==':'||s[0]==';'){
     s1=CopyStr(s+1);delete[]s;s=s1;s1=NULL;
     SimplifyStr(s);if(!s[0]||!strcmp(s,"Error")){goto fin;}
   }
+  // Case 1: Formula = Integer or decimal litteral, or predefined constant litteral (pi)
   if(IsTNumeric(s)){op=Num;ValC=atof(s);mmb1=NULL;mmb2=NULL;goto fin;};
   if(EqStr(s,"pi")||EqStr(s,"PI")||EqStr(s,"Pi"))
     {op=Num;ValC=3.141592653589793238462643383279L;mmb1=NULL;mmb2=NULL;goto fin;};
+  // Case 2: Formula = Variable with a name that is longer than a matching user defined or standard
+  //         function (Note: remaining chars are ignored if any !).
 	if(IsFunction(s,0,nfuncp,ppfuncp)<IsVar(s,0,nvar,ppvarp))
 		for(i=0;i<nvar;i++)if(EqStr(s,(*(ppvarp+i))->name))
 		{pvar=ppvarp[i];pvarval=pvar->pval;op=Var;mmb1=NULL;mmb2=NULL;goto fin;};
+  // Case 3: Something else.
 	for(k=0;s[k];k++){
+    // Jump over a (...) block.
     if(s[k]=='('){k=SearchCorOpenbracket(s,k);if(k==-1)break;continue;};
+    // Detect a function (user defined or standard one), with a name that is longer
+    // than the one of any matching variable => add a : or ; at the end of its name
+    // (; if f(...) notation used, : if ????)
     if((l=IsFunction(s,k,nfuncp,ppfuncp))&&l>=IsVar(s,k,nvar,ppvarp)){
       i=k+l;while(s[i]==' ')i++;
       if(s[i]=='('){
@@ -543,38 +663,49 @@ ROperation::ROperation(char*sp,int nvar,PRVar*ppvarp,int nfuncp,PRFunction*ppfun
       }else if(s[i]!=':'&&s[i]!=';'){InsStr(s,i,':');k=i;}
     }
   }
+  // Enclose any number, constant (Pi) and var name between parenthesis,
+  // and remove any (useless) space, tab or new line.
 	IsolateNumbers(s,nvar,ppvarp,nfuncp,ppfuncp);
 	if(nvar)IsolateVars(s,nvar,ppvarp,nfuncp,ppfuncp);
   SupprSpaces(s);
+  // Case 3a: "," binary operator (Juxtaposition)
   i=SearchOperator(s,Juxt);
   if(i!=-1){s1=MidStr(s,0,i-1);s2=MidStr(s,i+1,strlen(s)-1);
   op=Juxt;mmb1=new ROperation(s1,nvar,ppvarp,nfuncp,ppfuncp);
   mmb2=new ROperation(s2,nvar,ppvarp,nfuncp,ppfuncp);goto fin;
   };
+  // Case 3b: "+" binary operator (Addition)
   i=SearchOperator(s,Add);
   if(i!=-1){s1=MidStr(s,0,i-1);s2=MidStr(s,i+1,strlen(s)-1);
   op=Add;mmb1=new ROperation(s1,nvar,ppvarp,nfuncp,ppfuncp);
   mmb2=new ROperation(s2,nvar,ppvarp,nfuncp,ppfuncp);goto fin;
   };
+  // Case 3c: "-" binary operator (Substraction)
   i=SearchOperator(s,Sub);
   if(i!=-1){
     s1=MidStr(s,0,i-1);s2=MidStr(s,i+1,strlen(s)-1);
     op=Sub;mmb1=new ROperation(s1,nvar,ppvarp,nfuncp,ppfuncp);
     mmb2=new ROperation(s2,nvar,ppvarp,nfuncp,ppfuncp);goto fin;
   };
+  // Case 3d: "-" unary operator (Negation)
   if(s[0]=='-'){s2=MidStr(s,1,strlen(s)-1);
   op=Opp;mmb1=NULL;
   mmb2=new ROperation(s2,nvar,ppvarp,nfuncp,ppfuncp);goto fin;
   };
+  // Enclose function "calls" between parenthesis
   for(i=0;s[i];i++){
+    // Jump over a (...) block.
 		if(s[i]=='('){i=SearchCorOpenbracket(s,i);if(i==-1)break;continue;};
+    // Detecting a function "call" :
 		if(IsFunction(s,i,nfuncp,ppfuncp)){
-			k=i+IsFunction(s,i,nfuncp,ppfuncp);while(s[k]==' ')k++;
+			k=i+IsFunction(s,i,nfuncp,ppfuncp);while(s[k]==' ')k++; // Ignore spaces (Is it usefull, as SupprSpaces was called before ?)
+      // f(...) notation => enclose it between parenthesis (=> "(f(...))" )
 			if(s[k]==';'){
 				//	s=DelStr(s,k);
 				j=k;while(s[j]!='(')j++;
 				j=SearchCorOpenbracket(s,j);
 				if(j!=-1){InsStr(s,j,')');InsStr(s,i,'(');i=j+2;}
+      // ??? => enclose it between parenthesis (=> "(???)" )
 			}else if(s[k]==':'){
 				//	s=DelStr(s,k);
 				for(j=k;s[j];j++)
@@ -591,8 +722,10 @@ ROperation::ROperation(char*sp,int nvar,PRVar*ppvarp,int nfuncp,PRFunction*ppfun
 			}
 		}
   }
+  // Add explicit multiply operator "*" anywhere implicit ( (...)<here>(...) )
   for(i=0;s[i]&&s[i+1];i++)if(s[i]==')'&&s[i+1]=='(')
     InsStr(s,++i,'*');
+  // Case 3e: Standard or user defined function
   if(s[0]=='('&&SearchCorOpenbracket(s,0)==(int)strlen(s)-1){
     if(CompStr(s,1,"exp")){op=Exp;s2=MidStr(s,4,strlen(s)-2);}
     else if(CompStr(s,1,"abs")){op=Abs;s2=MidStr(s,4,strlen(s)-2);}
@@ -622,21 +755,25 @@ ROperation::ROperation(char*sp,int nvar,PRVar*ppvarp,int nfuncp,PRFunction*ppfun
 		if(op==Fun)if(mmb2->NMembers()!=pfunc->nvars){op=ErrOp;mmb1=NULL;mmb2=NULL;goto fin;}
     goto fin;
   };
+  // Case 3f: "*" binary operator (Multiplication)
   i=SearchOperator(s,Mult);
   if(i!=-1){s1=MidStr(s,0,i-1);s2=MidStr(s,i+1,strlen(s)-1);
   op=Mult;mmb1=new ROperation(s1,nvar,ppvarp,nfuncp,ppfuncp);
   mmb2=new ROperation(s2,nvar,ppvarp,nfuncp,ppfuncp);goto fin;
   };
+  // Case 3g: "/" binary operator (Division)
   i=SearchOperator(s,Div);
   if(i!=-1){s1=MidStr(s,0,i-1);s2=MidStr(s,i+1,strlen(s)-1);
   op=Div;mmb1=new ROperation(s1,nvar,ppvarp,nfuncp,ppfuncp);
   mmb2=new ROperation(s2,nvar,ppvarp,nfuncp,ppfuncp);goto fin;
   };
+  // Case 3h: "^" binary operator (Power)
   i=SearchOperator(s,Pow);
   if(i!=-1){s1=MidStr(s,0,i-1);s2=MidStr(s,i+1,strlen(s)-1);
   op=Pow;mmb1=new ROperation(s1,nvar,ppvarp,nfuncp,ppfuncp);
   mmb2=new ROperation(s2,nvar,ppvarp,nfuncp,ppfuncp);goto fin;
   };
+  // Case 3i: "#" binary operator (Square or N>2 th root)
   i=SearchOperator(s,NthRoot);
   if(i!=-1){s1=MidStr(s,0,i-1);s2=MidStr(s,i+1,strlen(s)-1);
   if(i==0||s[i-1]!=')')
@@ -644,12 +781,17 @@ ROperation::ROperation(char*sp,int nvar,PRVar*ppvarp,int nfuncp,PRFunction*ppfun
       {op=NthRoot;mmb1=new ROperation(s1,nvar,ppvarp,nfuncp,ppfuncp);};
   mmb2=new ROperation(s2,nvar,ppvarp,nfuncp,ppfuncp);goto fin;
   };
+  // Case 3k: "E" binary operator (power of 10)
   i=SearchOperator(s,E10);
   if(i!=-1){s1=MidStr(s,0,i-1);s2=MidStr(s,i+1,strlen(s)-1);
   op=E10;mmb1=new ROperation(s1,nvar,ppvarp,nfuncp,ppfuncp);
   mmb2=new ROperation(s2,nvar,ppvarp,nfuncp,ppfuncp);goto fin;
   };
+
+  // Other cases: Error.
   op=ErrOp;mmb1=NULL;mmb2=NULL;
+
+  //
 fin:
 	BuildCode();
 	delete[]s;if(s1!=NULL)delete[] s1;if(s2!=NULL)delete[]s2;
@@ -677,6 +819,7 @@ int operator==(const RFunction& f1,const RFunction& f2)
   if(f1.type!=f2.type)return 0;
   if(f1.type==-1)return 1; // Nonfunction==nonfunction
   if(f1.type==0)return (f1.pfuncval==f2.pfuncval&&EqStr(f1.name,f2.name));
+  if(f1.type==2)return (f1.pfuncobjval==f2.pfuncobjval&&EqStr(f1.name,f2.name));
   if(f1.op!=f2.op)return 0;
   if(!EqStr(f1.name,f2.name))return 0;
   if(f1.nvars!=f2.nvars)return 0;
@@ -761,7 +904,7 @@ signed char ROperation::HasError(const ROperation*pop) const
 
 int ROperation::NMembers() const //Number of members for an operation like a,b,c...
 {
-  if(op==Fun)return(pfunc->type==1?pfunc->op.NMembers():pfunc->type==0?1:0);
+  if(op==Fun)return(pfunc->type==1?pfunc->op.NMembers():pfunc->type==0?1:pfunc->type==2?pfunc->nvars:0);
   if(op!=Juxt)return 1;else if(mmb2==NULL)return 0;else return 1+mmb2->NMembers();
 }
 
@@ -823,7 +966,7 @@ ROperation ROperation::Diff(const RVar& var) const
   case Asin:return(mmb2->Diff(var)/sqrt(1-((*mmb2)^2)));
   case Acos:return(-mmb2->Diff(var)/sqrt(1-((*mmb2)^2)));
   case Abs:return(mmb2->Diff(var)*(*mmb2)/(*this));
-  case Fun:if(pfunc->type==-1||pfunc->type==0)return ErrVal;
+  case Fun:if(pfunc->type==-1||pfunc->type==0||pfunc->type==2)return ErrVal;
     if(pfunc->nvars==0)return 0.;
     else if(pfunc->op.NMembers()>1){
       j=pfunc->op.NMembers();
@@ -866,8 +1009,8 @@ char* ROperation::Expr() const
   if(mmb2!=NULL){s2=mmb2->Expr();n+=strlen(s2);g=IsFunction(mmb2->op);}
   s=new char[n];
   switch(op){
-  case Num:return ValToStr(ValC);
+  case Num:delete[]s;return ValToStr(ValC);
-  case Var:return CopyStr(pvar->name);
+  case Var:delete[]s;return CopyStr(pvar->name);
   case Juxt:sprintf(s,"%s , %s",s1,s2);break;
   case Add:
     f=f||(mmb1->op==Juxt);
@@ -982,7 +1125,7 @@ char* ROperation::Expr() const
   case Fun:
     sprintf(s,"%s(%s)",pfunc->name,s2);
     break;
-  default:return CopyStr("Error");
+  default:delete[]s;return CopyStr("Error");
   };
   if(s1!=NULL)delete[] s1;if(s2!=NULL)delete[] s2;
   return s;
@@ -1158,6 +1301,7 @@ void ROperation::BuildCode()
   if(pvals!=NULL){delete[]pvals;pvals=NULL;}//does not delete pvals[0] in case it was to be deleted... (no way to know)
   if(ppile!=NULL){delete[]ppile;ppile=NULL;}
   if(pfuncpile!=NULL){delete[]pfuncpile;pfuncpile=NULL;}
+
   switch(op){
   case ErrOp:pinstr=new pfoncld[2];pinstr[0]=&NextVal;pinstr[1]=NULL;
     pvals=new double*[2];pvals[0]=new double(ErrVal);pvals[1]=NULL;

mathexpr/mathexpr/mathexpr.h

@@ -1,6 +1,6 @@
 /*
 
-mathexpr.h version 2.0
+mathexpr.h version 2.1
 
 Copyright (c) 1997-2000 Yann OLLIVIER
 
@@ -12,6 +12,12 @@ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLI
 
 */
 
+/* 2009 changes by Jean-Philippe Meuret <jpmeuret@free.fr> for Qatsh
+   - added EFunction class to support external function with any number of parameters
+   - ROperation::ROperation(const char*,int,PRVar*,int,PRFunction*) :
+     changed 1st arg from 'char*' to 'const char*' for GCC 4.2 (deprecated conversion)
+ */
+
 #ifndef _MATHEXPR_H
 #define _MATHEXPR_H
 
@@ -79,7 +85,7 @@ class ROperation{
   ROperation(const ROperation&);
   ROperation(double);
   ROperation(const RVar&);
-  ROperation(char*sp,int nvarp=0,PRVar*ppvarp=NULL,int nfuncp=0,PRFunction*ppfuncp=NULL);
+  ROperation(const char*sp,int nvarp=0,PRVar*ppvarp=NULL,int nfuncp=0,PRFunction*ppfuncp=NULL);
   ~ROperation();
   double Val() const;
   signed char ContainVar(const RVar&) const;
@@ -114,15 +120,30 @@ class ROperation{
   ROperation Substitute(const RVar&,const ROperation&) const;
 };
 
+class EFunction{
+public:
+  unsigned nvars;
+  double* pvars;
+  EFunction(unsigned nvarsp);
+  virtual ~EFunction();
+  double operator()(double* pvarsp);
+  double operator()(double var1p, ...); // Warning: Only double vars supported
+  // Compute function value from pvars[] after operator () filled it
+  // => (re)implement only this function
+  virtual double Val() = 0;
+};
+
 class RFunction{
   double*buf;
 public:
-  signed char type;
+  signed char type; //Compute the value through: 2=>pfuncobjval, 1=>op, 0=>pfuncval, -1=>Can't do it.
   double ((*pfuncval)(double));
+  EFunction* pfuncobjval;
   ROperation op;int nvars;RVar** ppvar;
   char*name;
   RFunction();
   RFunction(double ((*)(double)));
+  RFunction(EFunction& efunc);
   RFunction(const ROperation& opp,RVar* pvarp);
   RFunction(const ROperation& opp,int nvarsp,RVar**ppvarp);
   RFunction(const RFunction&);