node.h

根据LDPC码中码子的构造方法中的PEG算法

/*******************************************
 *
 * general node used in a factor graph
 *
 *******************************************/

#ifndef NODE
#define NODE

#include <stddef.h>
#include <stdio.h>

class Node {

protected:

  // name of this node
  char name[20];

  // identification number
  int id;

  // number of neighbours of this node
  int numNeighbours;

  // actual messages flowing out of this node
  double *(*outMessages);
  
public:
  
  // array of pointers to all neighbours
  Node *(*neighbours);

  // array of port numbers of this node with respect to the according neighbour
  int *portNumbers;


  // default constructor
  Node(void);

  // constructor
  Node(const char *name, int id, int numNeighbours);

  // destructor
  virtual ~Node(void);

  // connects two nodes in the following way:
  // (node1, port1) <--> (node2, port2)
  static void connect(Node *node1, Node *node2, int port1, int port2, int alphabetSize);

  // disconnects two nodes
  // - return value:  0, if the two nodes were connected before
  //                 -1, otherwise
  static int disconnect(Node *node1, Node *node2);

  // disconnects this node and the one at the specified port
  // - return value:  0, if the two nodes were connected before
  //                 -1, otherwise
  int disconnect(int port);

  // returns the outflowing message at the specified port
  double *getOutMessage(int port);

  // updates the outflowing message at the specified port
  virtual void update(int port) = 0;

  // updates all outflowing messages of this node
  virtual void updateAll(void);

  // resets all outflowing messages
  virtual void reset(void) = 0;

  const char *getName(void);

  int getID(void);

  int getNumNeighbours(void);

  int getPortNumber(int neighbour);

  // issues a textual description of the current configuration of this node to standard output
  // (for debugging purposes)
  virtual void draw(void);

  // test method
  static void test(void);

};

#endif