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Display diff logic optimization and min cost flow in smt2 format

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Anh-Dung Phan 2013-11-25 02:15:21 +01:00
parent fff3a1aae5
commit 8fe50ff2d9
2 changed files with 83 additions and 32 deletions
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6
src/smt/network_flow.h
View file

@ -279,13 +279,15 @@ namespace smt {
void update_spanning_tree();
std::string display_spanning_tree();
bool edge_in_tree(edge_id id) const;
bool check_well_formed();
bool check_optimal();
void display(std::ofstream & os);
void display_dual(std::ofstream & os);
void display_spanning_tree(std::ofstream & os);
public:
network_flow(graph & g, vector<fin_numeral> const & balances);

109
src/smt/network_flow_def.h
View file

@ -40,29 +40,80 @@ 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 << "(assert (= v0 0))" << std::endl;
tout << "(maximize (+";
for (unsigned i = 0; i < balances.size(); ++i) {
tout << " (* " << balances[i] << " v" << i << ")";
};
tout << "))" << std::endl;
tout << "(optimize)" << std::endl;
TRACE("network_flow", {
tout << "Different logic optimization:" << std::endl;
display_dual(tout);
tout << "Minimum cost flow:" << std::endl;
display(tout);
};);
m_step = 0;
m_tree = alloc(basic_spanning_tree<Ext>, m_graph);
}
template<typename Ext>
void network_flow<Ext>::display(std::ofstream & os) {
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];
os << "(declare-fun y_" << e.get_source() << "_" << e.get_target() << " () Real)" << std::endl;
};
for (unsigned i = 0; i < m_graph.get_num_edges(); ++i) {
edge const & e = es[i];
os << "(assert (>= y_" << e.get_source() << "_" << e.get_target() << " 0))" << std::endl;
};
for (unsigned i = 0; i < m_graph.get_num_nodes(); ++i) {
bool initialized = false;
for (unsigned j = 0; j < m_graph.get_num_edges(); ++j) {
edge const & e = es[j];
if (e.get_target() == i || e.get_source() == i) {
if (!initialized) {
os << "(assert (= (+";
}
initialized = true;
if (e.get_target() == i) {
os << " y_" << e.get_source() << "_" << e.get_target();
}
else {
os << " (- y_" << e.get_source() << "_" << e.get_target() << ")";
}
}
}
if(initialized) {
os << " " << m_balances[i] << ") 0))" << std::endl;
}
}
os << "(minimize (+";
for (unsigned i = 0; i < m_graph.get_num_edges(); ++i) {
edge const & e = es[i];
os << " (* " << e.get_weight() << " y_" << e.get_source() << "_" << e.get_target() << ")";
};
os << "))" << std::endl;
os << "(optimize)" << std::endl;
}
template<typename Ext>
void network_flow<Ext>::display_dual(std::ofstream & os) {
for (unsigned i = 0; i < m_graph.get_num_nodes(); ++i) {
os << "(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];
os << "(assert (<= (- v" << e.get_source() << " v" << e.get_target() << ") " << e.get_weight() << "))" << std::endl;
};
os << "(assert (= v0 0))" << std::endl;
os << "(maximize (+";
for (unsigned i = 0; i < m_balances.size(); ++i) {
os << " (* " << m_balances[i] << " v" << i << ")";
};
os << "))" << std::endl;
os << "(optimize)" << std::endl;
}
template<typename Ext>
void network_flow<Ext>::initialize() {
TRACE("network_flow", tout << "initialize...\n";);
@ -106,7 +157,7 @@ namespace smt {
TRACE("network_flow", {
tout << pp_vector("Potentials", m_potentials, true) << pp_vector("Flows", m_flows);
});
TRACE("network_flow", tout << "Spanning tree:\n" << display_spanning_tree(););
TRACE("network_flow", tout << "Spanning tree:\n"; display_spanning_tree(tout););
SASSERT(check_well_formed());
}
@ -227,7 +278,7 @@ namespace smt {
m_states[m_leave_id] = LOWER;
update_spanning_tree();
update_potentials();
TRACE("network_flow", tout << "Spanning tree:\n" << display_spanning_tree(););
TRACE("network_flow", tout << "Spanning tree:\n"; display_spanning_tree(tout););
SASSERT(check_well_formed());
}
}
@ -316,32 +367,30 @@ namespace smt {
}
template<typename Ext>
std::string network_flow<Ext>::display_spanning_tree() {
void network_flow<Ext>::display_spanning_tree(std::ofstream & os) {
++m_step;;
std::ostringstream oss;
std::string prefix = "T";
prefix.append(std::to_string(m_step));
prefix.append("_");
unsigned root = m_graph.get_num_nodes() - 1;
for (unsigned i = 0; i < root; ++i) {
oss << prefix << i << "[shape=circle,label=\"" << prefix << i << " [";
oss << m_potentials[i] << "/" << m_balances[i] << "]\"];\n";
os << prefix << i << "[shape=circle,label=\"" << prefix << i << " [";
os << m_potentials[i] << "/" << m_balances[i] << "]\"];\n";
}
oss << prefix << root << "[shape=doublecircle,label=\"" << prefix << root << " [";
oss << m_potentials[root] << "/" << m_balances[root] << "]\"];\n";
os << prefix << root << "[shape=doublecircle,label=\"" << prefix << root << " [";
os << m_potentials[root] << "/" << m_balances[root] << "]\"];\n";
unsigned num_edges = m_graph.get_num_edges();
for (unsigned i = 0; i < num_edges; ++i) {
oss << prefix << m_graph.get_source(i) << " -> " << prefix << m_graph.get_target(i);
os << prefix << m_graph.get_source(i) << " -> " << prefix << m_graph.get_target(i);
if (m_states[i] == BASIS) {
oss << "[color=red,penwidth=3.0,label=\"" << m_flows[i] << "/" << m_graph.get_weight(i) << "\"];\n";
os << "[color=red,penwidth=3.0,label=\"" << m_flows[i] << "/" << m_graph.get_weight(i) << "\"];\n";
}
else {
oss << "[label=\"" << m_flows[i] << "/" << m_graph.get_weight(i) << "\"];\n";
os << "[label=\"" << m_flows[i] << "/" << m_graph.get_weight(i) << "\"];\n";
}
}
oss << std::endl;
return oss.str();
os << std::endl;
}
}