/**
* Receive all messages and compute the new belief.
*/
inline void update_belief(const vertex_type& vertex,
StateManager& state) {
// Get the belief from the state manager
belief_type* blf = state.checkout_belief(vertex);
// Wipe out the old value for the belief
if(vertex.is_variable()) {
*blf = 1;
} else if(vertex.is_factor()) {
*blf = vertex.factor();
} else {
assert(false);
}
// For each of the neighbor variables
foreach(const vertex_type& vertex_source, state.neighbors(vertex)) {
// get the in message
message_type* in_msg =
state.try_checkout(vertex_source, vertex, Reading);
if(in_msg != NULL) {
// Combine the in_msg with the destination factor
blf->combine_in(*in_msg, csr_.dot_op);
// return the message to the state manager
state.checkin(vertex_source, vertex, in_msg);
// normalize the belief
blf->normalize();
}
}
// Do an extra normalization (just in case no messages were
// available)
blf->normalize();
// ASSERT WE BLF IS A VALID DISTRIBUTION (we should check this)
// Save the belief
state.checkin_belief(vertex, blf);
}// End of update belief
/**
* Receive all messages into the factor f and compute all new
* outbound messages.
*/
void send_messages(const vertex_type& vertex,
StateManager& state) {
// Get the belief from the state manager
belief_type* blf;
// Wipe out the old value for the belief
if(vertex.is_variable()) {
blf = state.checkout_belief(vertex);
(*blf) = 1;
blf->normalize();
// std::cout << "var\n";
} else if(vertex.is_factor()) {
blf = new belief_type();
(*blf) = vertex.factor();
blf->normalize();
// std::cout << "fact\n";
} else {
assert(false);
}
// std::cout << blf->arguments()<<"\n";
std::vector<vertex_type> neighbors;
std::vector<message_type*> neighbor_inmsg;
// For each of the neighbor variables
// std::cout << (*blf);
foreach(const vertex_type& vertex_source, state.neighbors(vertex)) {
// get the in message
message_type* in_msg =
state.checkout(vertex_source, vertex, Reading);
// remember the messages and which neighbor it came from
neighbors.push_back(vertex_source);
neighbor_inmsg.push_back(in_msg);
// Combine the in_msg with the destination factor
if (vertex.is_variable()) {
assert(in_msg->arguments().size() == 1);
assert(in_msg->arguments().contains(&(vertex.variable())));
}
else if (vertex.is_factor()) {
assert(blf->arguments().contains(&(vertex_source.variable())));
}
blf->combine_in(*in_msg, csr_.dot_op);
// std::cout << "Include: " << (*in_msg);
// normalize the belief
blf->normalize();
// std::cout << (*blf);
}
//std::cout<< "------------------------------------";
// compute the outgoing messages
message_type oldmessage;
for (size_t i = 0; i< neighbors.size(); ++i) {
message_type* out_msg = state.checkout(vertex, neighbors[i], Writing);
// divide out the incoming message here
oldmessage = (*out_msg);
// std::cout << "Exclude: " << (*neighbor_inmsg[i]);
if (neighbors[i].is_variable()) {
(*out_msg) = blf->collapse(csr_.cross_op, make_domain(&neighbors[i].variable()));
out_msg->combine_in(*(neighbor_inmsg[i]), divides_op);
}
else {
(*out_msg) = combine(*blf, *(neighbor_inmsg[i]), divides_op);
}
out_msg->normalize();
// std::cout<<*out_msg;
// Save the damped message to the destination message
// lets only damp the factor to variable updates
// otherwise we will 'doubly damp' the messages in a pairwise MRF
if(neighbors[i].is_variable()) {
(*out_msg) = weighted_update(*out_msg, oldmessage, damping_);
}
// checkin the final message to the state manager
state.checkin(neighbors[i], vertex, neighbor_inmsg[i]);
state.checkin(vertex, neighbors[i], out_msg);
}
// getchar();
// lets checkin the belief while we are at it
if (vertex.is_variable()) state.checkin_belief(vertex,blf);
else delete blf;
state.mark_visited(vertex);
}