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Update basic spanning tree to be on par with threaded one

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Anh-Dung Phan 2013-11-22 13:44:12 -08:00
parent 7bc7a61a40
commit 37f5628824
6 changed files with 63 additions and 26 deletions
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3
src/smt/network_flow.h
View file

@ -71,7 +71,6 @@ namespace smt {
edge_id & m_enter_id;
public:
pivot_rule_impl() {}
pivot_rule_impl(graph & g, vector<numeral> & potentials,
svector<edge_state> & states, edge_id & enter_id)
: m_graph(g),
@ -79,7 +78,7 @@ namespace smt {
m_states(states),
m_enter_id(enter_id) {
}
bool choose_entering_edge() {return false;};
virtual bool choose_entering_edge() = 0;
};
class first_eligible_pivot : public pivot_rule_impl {

28
src/smt/network_flow_def.h
View file

@ -40,6 +40,24 @@ namespace smt {
m_graph.add_edge(e.get_target(), e.get_source(), e.get_weight(), explanation());
}
}
TRACE("network_flow", {
tout << "Solving different logic optimization problem:" << std::endl;
for (unsigned i = 0; i < m_graph.get_num_nodes(); ++i) {
tout << "(declare-fun v" << i << " () Real)" << std::endl;
}
vector<edge> const & es = m_graph.get_all_edges();
for (unsigned i = 0; i < m_graph.get_num_edges(); ++i) {
edge const & e = es[i];
tout << "(assert (<= (- v" << e.get_source() << " v" << e.get_target() << ") " << e.get_weight() << "))" << std::endl;
};
tout << "(maximize (+ ";
for (unsigned i = 0; i < balances.size(); ++i) {
tout << "(* " << balances[i] << " v" << i << ") ";
};
tout << "))" << std::endl;
tout << "(optimize)" << std::endl;
};);
m_step = 0;
m_tree = alloc(basic_spanning_tree<Ext>, m_graph);
}
@ -130,7 +148,7 @@ namespace smt {
}
template<typename Ext>
bool network_flow<Ext>::choose_leaving_edge() {
bool network_flow<Ext>::choose_leaving_edge() {
TRACE("network_flow", tout << "choose_leaving_edge...\n";);
node src = m_graph.get_source(m_enter_id);
node tgt = m_graph.get_target(m_enter_id);
@ -155,10 +173,10 @@ namespace smt {
tout << "Found leaving edge " << m_leave_id;
tout << " between node " << m_graph.get_source(m_leave_id);
tout << " and node " << m_graph.get_target(m_leave_id) << " with delta = " << *m_delta << "...\n";
});
});
return true;
}
TRACE("network_flow", tout << "Can't find a leaving edge... The problem is unbounded.\n";);
TRACE("network_flow", tout << "Can't find a leaving edge... The problem is unbounded.\n";);
return false;
}
@ -179,7 +197,7 @@ namespace smt {
pivot = alloc(best_eligible_pivot, m_graph, m_potentials, m_states, m_enter_id);
break;
case CANDIDATE_LIST:
pivot = alloc(best_eligible_pivot, m_graph, m_potentials, m_states, m_enter_id);
pivot = alloc(candidate_list_pivot, m_graph, m_potentials, m_states, m_enter_id);
break;
default:
UNREACHABLE();
@ -208,7 +226,7 @@ namespace smt {
}
else {
m_states[m_leave_id] = m_states[m_leave_id] == LOWER ? UPPER : LOWER;
}
}
}
TRACE("network_flow", tout << "Found optimal solution.\n";);
SASSERT(check_optimal());

1
src/smt/spanning_tree.h
View file

@ -74,7 +74,6 @@ namespace smt {
private:
graph * m_tree_graph;
public:
basic_spanning_tree(graph & g);
void initialize(svector<edge_id> const & tree);

23
src/smt/spanning_tree_def.h
View file

@ -421,8 +421,7 @@ namespace smt {
template<typename Ext>
void basic_spanning_tree<Ext>::initialize(svector<edge_id> const & tree) {
m_tree_graph = alloc(graph);
m_tree.reset();
m_tree.append(tree);
m_tree = tree;
unsigned num_nodes = m_graph.get_num_nodes();
for (unsigned i = 0; i < num_nodes; ++i) {
m_tree_graph->init_var(i);
@ -464,11 +463,25 @@ namespace smt {
m_tree_graph->bfs_undirected(root, m_pred, m_depth);
m_tree_graph->dfs_undirected(root, m_thread);
for (node x = m_thread[root]; x != root; x = m_thread[x]) {
vector<edge> const & tree_edges = m_tree_graph->get_all_edges();
for (unsigned i = 0; i < tree_edges.size(); ++i) {
edge const & e = tree_edges[i];
dl_var src = e.get_source();
dl_var tgt = e.get_target();
edge_id id;
VERIFY(m_graph.get_edge_id(x, m_pred[x], id));
m_tree[x] = id;
VERIFY(m_graph.get_edge_id(src, tgt, id));
SASSERT(tgt == m_pred[src] || src == m_pred[tgt]);
if (tgt == m_pred[src]) {
m_tree[src] = id;
}
else {
m_tree[tgt] = id;
}
}
node p = m_graph.get_source(enter_id);
node q = m_graph.get_target(enter_id);
m_root_t2 = p == m_pred[q] ? q : p;
}
}

1
src/smt/theory_diff_logic.h
View file

@ -192,7 +192,6 @@ namespace smt {
vector<objective_term> m_objectives;
vector<rational> m_objective_consts;
vector<vector<numeral> > m_objective_assignments;
numeral m_objective_value;
// Set a conflict due to a negative cycle.
void set_neg_cycle_conflict();

33
src/smt/theory_diff_logic_def.h
View file

@ -1007,9 +1007,9 @@ inf_eps_rational<inf_rational> theory_diff_logic<Ext>::maximize(theory_var v) {
IF_VERBOSE(1,
for (unsigned i = 0; i < objective.size(); ++i) {
verbose_stream() << "coefficient " << objective[i].second << " of theory_var " << objective[i].first << "\n";
verbose_stream() << "Coefficient " << objective[i].second << " of theory_var " << objective[i].first << "\n";
}
verbose_stream() << "free coefficient " << m_objective_consts[v] << "\n";);
verbose_stream() << "Free coefficient " << m_objective_consts[v] << "\n";);
// Objective coefficients now become balances
vector<fin_numeral> balances(m_graph.get_num_nodes());
@ -1018,24 +1018,33 @@ inf_eps_rational<inf_rational> theory_diff_logic<Ext>::maximize(theory_var v) {
fin_numeral balance(objective[i].second);
balances[objective[i].first] = balance;
}
network_flow<GExt> net_flow(m_graph, balances);
bool is_optimal = net_flow.min_cost();
if (is_optimal) {
vector<numeral> potentials;
m_objective_value = net_flow.get_optimal_solution(potentials, true);
std::cout << "Objective value of var " << v << ": " << m_objective_value << std::endl;
m_objective_assignments[v] = potentials;
numeral objective_value = net_flow.get_optimal_solution(m_objective_assignments[v], true) + numeral(m_objective_consts[v]);
IF_VERBOSE(1, verbose_stream() << "Optimal value of objective " << v << ": " << objective_value << std::endl;);
DEBUG_CODE(
numeral initial_value = numeral(m_objective_consts[v]);
for (unsigned i = 0; i < objective.size(); ++i) {
initial_value += fin_numeral(objective[i].second) * m_graph.get_assignment(objective[i].first);
}
IF_VERBOSE(1, verbose_stream() << "Initial value of objective " << v << ": " << initial_value << std::endl;);
SASSERT(objective_value >= initial_value););
vector<numeral> & current_assigments = m_objective_assignments[v];
SASSERT(!current_assigments.empty());
TRACE("network_flow",
for (unsigned i = 0; i < potentials.size(); ++i) {
tout << "v" << i << " -> " << potentials[i] << "\n";
for (unsigned i = 0; i < current_assigments.size(); ++i) {
tout << "v" << i << " -> " << current_assigments[i] << std::endl;
});
rational r = m_objective_value.get_rational().to_rational();
rational i = m_objective_value.get_infinitesimal().to_rational();
rational r = objective_value.get_rational().to_rational();
rational i = objective_value.get_infinitesimal().to_rational();
return inf_eps_rational<inf_rational>(inf_rational(r, i));
}
else {
std::cout << "Unbounded objective" << std::endl;
IF_VERBOSE(1, verbose_stream() << "Unbounded objective" << std::endl;);
return inf_eps_rational<inf_rational>::infinity();
}
}