/**************************/
/* Type definitions Tree2 */
/**************************/


/***************/
/* Basic types */
/***************/

typedef  char	Boolean, *String;


/*********/
/* Items */
/*********/

typedef  union  _attribute_value
	 {
	    DiscrValue	_discr_val;
	    float	_cont_val;
	 }
	 	AttValue, *Description;
		
typedef  Description ItemRec;             

#define  CVal(Case,Attribute)   Case[Attribute]._cont_val
         /* Value of the continuous Attribute of ItemRec Case */
#define  DVal(Case,Attribute)   Case[Attribute]._discr_val
         /* Value of the discrete Attribute of ItemRec Case */


/*****************************************************/   
/* Types for constructing the optimal interval split */   
/*****************************************************/

/* Segment of an interval split*/
typedef  struct _segment        
         {
	    ItemCount   Freq, Error;
	    float       Threshold;          /* lefthand threshold, included in the segment */
	    ClassNo     BestClass;          /* class of the segment */
	 }
	       Segment;
	       
/* An interval split */	       
typedef  struct _intervals 
         {
	    ItemCount   Freq, Error;
	    ClassNo     BestClass;
	    int       NoIntervals;
	    Segment     *Split;             /* Split[0..NoIntervals],
	                                       Split[0] contains the information on
					          unknown attribute values */
	 }
	       IntervalSplit;

/* All possible interval splits */	       
typedef  IntervalSplit  ***AllIntervals;  /* IntSpl[c1][k][c2] denotes the optimal 
	                                     split into k intervals such that 
					     the leftmost interval has class c1 
					     and the rightmost interval has class c2 */  

/* List of AllIntervals */	        /* A proper AllList is sorted on the */    
typedef  struct _l_record *AllList;     /* y-values and no y-value appears */
typedef  struct _l_record               /* twice in an AllList. The last element of */
         {                              /* an AllList has y-value Infinity. */
	    float          y_val;          /* y-value */
	    AllIntervals   allint_L;       /* Splits of the */
	    AllIntervals   allint_U;       /*    x-value */
	    AllList        next;
	 }
	       ALRecord;

/* List of AllLists */                           /* A proper Superlist is sorted */	       
typedef  struct _sl_record *SuperList;           /* on the x-values of its AllLists, */
typedef  struct _sl_record                       /* and the x-values of two AllLists in */
         {                                       /* the SuperList are distinct. */
	    AllList     alllist;
	    SuperList   next;
	 }
	       SLRecord;
	       
/* List of items */	       
typedef  struct _il_record *ItemList;
typedef  struct _il_record 
         {
	    ItemRec     item;
	    ItemList    next;
	 }      ILRecord;