(@ #include <math.h> @)

// this is the basic iterative algorithm for the computation of the 
// congestion Z at each step.

*operation* void iterate()
*wrapper* RoutingAlgorithm
  (@
     Ring* ring = get_ring();
     RoutingTable* rtable = get_routing_table();
     int max_iter = *get_max_iter();

     int i, count = 0;
     double Z, Z_prev;

     get_init()->initialize_util(ring);
//     cout << "\n\nPrinting the ring... \n";
//     ring->print_ring();
//     cout << "\n\nPrinting the routing table...\n";
//     rtable->print_routing_table();
     cout << "\n\nNow iterating and computing congestion Z...\n";

     for (i = 1; i <= max_iter; i++) {
       cout << "*********************  Iteration " << i << " ********************" << endl;
       cout << "a. computing proximities...\n";
       get_prox()->compute_proximities(rtable, ring);
       cout << "b. sorting the routing table...\n";
       rtable->sort_routing_table();
       cout << "c. computing probabilities...\n";
       get_prob()->compute_probabilities(rtable, ring);
       cout << "d. computing flows...\n";
       get_flow()->compute_flows(rtable);
       cout << "e. computing total flows\n";
       ring->compute_total_flows(rtable);
       //rtable->print_routing_table();
       cout << "f. looking for congestion Z...\n";
       Z = ring->congestion();
       cout << "    Z = " << Z << endl;
       if (i > 1 && fabs(Z - Z_prev) < 1e-5)
	 count++;
       else 
	 count = 0;
       if (count >= 4) break;
       cout << "g. computing utilization...\n";
       get_util()->compute_utilization(ring, Z, i+1);
       Z_prev = Z;
     }
     if (count >= 4) {
       cout << "\n\nCONVERGED to Z = " << Z << endl;
     }
     else {
       cout << "\n\nNO CONVERGENCE\n";
     }
   @)