tvelement.h

TV-tree的c实现源码

/* 
 
                  COPYRIGHT NOTICE
 
This material was developed by Christos Faloutsos and King-Ip Lin
at the University of Maryland, College Park, Department of Computer Science.
Permission is granted to copy this software, to redistribute it
on a nonprofit basis, and to use it for any purpose, subject to
the following restrictions and understandings.
 
1. Any copy made of this software must include this copyright notice
in full.
 
2. All materials developed as a consequence of the use of this
software shall duly acknowledge such use, in accordance with the usual
standards of acknowledging credit in academic research.
 
3. The authors have made no warranty or representation that the
operation of this software will be error-free or suitable for any
application, and they are under under no obligation to provide any
services, by way of maintenance, update, or otherwise.  The software
is an experimental prototype offered on an as-is basis.
 
4. Redistribution for profit requires the express, written permission
of the authors.
 
*/

// Author : $Author$
// Date : $Date$
// Id : $Id$
// $Id: element.h,v 1.2 1996/04/18 21:50:24 kilin Exp kilin $ 
// Elements to be indexing by the TV-tree
// bytearray : an array storing the byte pattern of the object to be stored
// noofbytes : number of bytes of the byte pattern
// vec : Currently expanded vector for the element

// The elmenet require three functions declare on the type to be indexed:
//
// gfeat(featno, bytearray) : Generate the featno-th feature (counting from 1)
//			    : if featno is 0 or less, will return the maximum
//			      number of features
//
// equal() : return TRUE if the two bytearray represent the same object 
//
// dist() : return the distance between two objects 

#define NO_OF_FEATURES 27

class Leaf_Element {

public:

  Leaf_Element();
  Leaf_Element(char *barray, int bytes);
  Leaf_Element(const Leaf_Element& ele);
  ~Leaf_Element();
  
  Leaf_Element& operator=(const Leaf_Element&);

  // Get the vector, expend if necessary
  // dim = number of dimensions wanted
  // store = TRUE : store the newly expanded vector to vec;
  TVector GetTVector(int dim, VCOM_TYPE (*gfeat)(int, char*), int store = TRUE);

  // Get the currently expanded vector
  TVector GetTVector();

  // Drop the last dimensions of the vector
  Leaf_Element& DropDim(int dimtodrop);

  // Get component no. (compno), start counting at 1
  // Call gfeat if necessary
  // store = TRUE : store the newly expanded vector to vec;
  VCOM_TYPE GetFeature(int feature, VCOM_TYPE (*gfeat)(int, char*), int store = TRUE);

  int Size() const;
  int ExpectedSize(int dim) const; // expected size of the element if it carries
			          // a dim dimensional vector
  int BytearraySize() const;

  int equal(const Leaf_Element& le, int (*eq)(char *, int, char *, int));
 
   // Return the byte array
   char* operator()();

   float Distance(const Leaf_Element& le, float (*dist)(char *, int, char *, int));

//   Leaf_Element& PreComputeFeature(int count, VCOM_TYPE (*gfeat)(int, char*));


private:

  TVector GenNewTVector(int noofnewfeature, VCOM_TYPE (*gfeat)(int, char*));

   char *bytearray;
   int noofbytes;  // size of the bytearray
   TVector vec;
};