/* Network.H * * The uncertainty program computes probabilities given a network * of dependencies and some examples. The Network class contains the * network, which is read in from a file. It also contains the examples * and some scratch variables needed for computation. * * Most of the below methods are associated with either the exact * algorithm, or the approximation algorithm. Some are used in both. *//* * Copyright 1994, Brown University, Providence, RI * See end of file for full copyright information */#include <iostream.h>#include "Node.H"class Network {   /********************  Overloaded Operators *********************/friend ostream& operator<<(ostream &o, Network &d);   // Print out the network   /********************  Approximation Algorithm *********************/   void initialize_values();   // Set up evidence in root nodes   void simulate();            // Simulate propagating values   void update_scores();       // Update scores with likelihood weighting   double sample_weight();     // Compute likelihood weighting of evidence   void set_evidence();        // Set evidence for nodes that have it   /********************  Exact Algorithm *********************/   void initialize_priors();   // Propagate the priors down the root nodes   void propagate();           // Propagate evidence up and down   /********************  General Stuff *********************/   int lookup_num(char *name); // Get the number of a node given its namepublic:   static Node **nodes;        // All the nodes in the network   static int num_nodes;       // The number of nodes in the network   static int do_approximate;  // Run the approximation algorithm? (If not,                               // then the user wants the exact algorithm)   static Node *lookup(char *name);  // Get a pointer to node given its name   EvidenceType *evidence;     // The evidence, which is an array indexed                               // by node number.   Network(istream& in);       // Construct a network from a file input   ~Network();                 // Destructor   void exact();               // Run the exact algorithm   void approximate(int iterations);  // Run the approximation algorithm};/* * Copyright 1994, Brown University, Providence, RI * * Permission to use and modify this software and its documentation for * any purpose other than its incorporation into a commercial product is * hereby granted without fee.  Permission to copy and distribute this * software and its documentation only for non-commercial use is also * granted without fee, provided, however, that the above copyright notice * appear in all copies, that both that copyright notice and this permission * notice appear in supporting documentation, that the name of Brown * University not be used in advertising or publicity pertaining to * distribution of the software without specific, written prior permission, * and that the person doing the distribution notify Brown University of * such distributions outside of his or her organization. Brown University * makes no representations about the suitability of this software for * any purpose.  It is provided "as is" without express or implied warranty. * Brown University requests notification of any modifications to this * software or its documentation. * * Send the following redistribution information: * *	Name: *	Organization: *	Address (postal and/or electronic): * * To: *	Software Librarian *	Computer Science Department, Box 1910 *	Brown University *	Providence, RI 02912 * *		or * *	brusd@cs.brown.edu * * We will acknowledge all electronic notifications. */