/*****************************************************************/
/* Definitions, variables, and routines in T2 which people might */
/* want to use their programs                                    */
/*****************************************************************/


/***************/
/* Global data */
/***************/


extern  int		MaxAtt,		/* max att number */
			MaxClass,	/* max class number */
			MaxDiscrVal;	/* max discrete values for any att */

extern  ItemNo		MaxItem;	/* max data item number */

extern  DiscrValue	*MaxAttVal;	/* number of values for each att [0..MaxAtt] 
                                           0 if attribute is continuous */

extern  char		*SpecialStatus;	/* special att treatment, [0..MaxAtt] */
                                        /* set to IGNORE if you don't want to split on
                                           this attribute */

extern  String		*ClassName,	/* class names [0..MaxClass] */
		  	*AttName,	/* att names [0..MaxAtt] */
		  	**AttValName,	/* att value names */
			FileName;	/* family name of files */


extern  ItemRec 	*Item;		/* data items [0..MaxItem] */

#define  Class(Case)		Case[MaxAtt+1]._discr_val
         /* Class of ItemRec Case */
#define  Weight(Case)           Case[MaxAtt+2]._cont_val
         /* Weight of ItemRec Case 
            can be modified by Weight(Case) = ... */


extern  int		MAXINTERVALS;	/* maximal number of intervals at 
                                           the bottom nodes */

/************/
/* Routines */
/************/

void CommandInput(int Argc, char* Argv[]);   /* reads the process options 
                                           In misc.c */

void GetNames();   /* Reads file FileName.data and initializes 
                         ClassName, AttName, AttValName, 
			 MaxAttVal, MaxAtt, MaxClass, MaxDiscrVal, SpecialStatus.
	              Taken from C4.5. 
                      In getnames.c */
	
void GetData(String Extension);   /* Reads file FileName.Extension and initializes
                                        Item, MaxItem.
			             Taken from C4.5. 
                                     In getdata.c */ 

Tree BuildTree(ItemNo Fp, ItemNo Lp, int Dep, ClassNo RootClass);
        /* Returns an optimal decision tree of depth at most Dep <= 2 
              for Item[Fp..Lp], Fp <= Lp.
	   RootClass is the class of the parent node, might be None. 
           In buildtree.c */
	
void PrintHeader();   /* Prints a header. Partly taken from C4.5. 
                         In output.c */

void InitializeData();   /* Initializes data structures used during the computation 
                            In init.c */

void PrintTree(Tree T);   
        /* Prints tree T. 
	   Essentially taken from C4.5, including Show(), ShowBranch(), MaxLine(). 
           In output.c */

void Evaluate(Tree T);   
        /* Evaluates tree T on Item[0..MaxItem] and prints the result.
	   Partly taken from C4.5. 
           In output.c */

ClassNo Classify(ItemRec It, Tree T);
        /* Returns the classification of It by T. 
           In misc.c */

Tree CopyTree(Tree T);   /* Returns a copy of tree T   
                            In init.c */
                
void ReleaseTree(Tree T);   /* Deletes tree T from memory 
                               In init.c */