void BruteForceOptMatching::checkAmbiguities(const BP& ia,
const FactorGraph& fg,
const ConnectedFactorGraph& graph,
McDArray<int>& ambiguities) {
for (int h = 0; h < graph.variables.size(); h++) {
McDArray<int> possibleAssignments;
getAssignmentsForVariable(graph.variables[h], possibleAssignments);
Factor belief =
ia.belief(Var(graph.variables[h], possibleAssignments.size() + 1));
float maxProb = belief.max();
int countSame = 0;
for (int k = 0; k < possibleAssignments.size() + 1; k++) {
float curProb = belief.get(k);
if (fabs(curProb - maxProb) < 0.1)
countSame++;
}
/////
cout << "\n Belief for var " << graph.variables[h] << "\n";
for (int k = 0; k < possibleAssignments.size() + 1; k++) {
float curProb = belief.get(k);
cout << curProb << " ";
}
cout << "\n";
////
if (countSame > 1) {
// oh no! We found an ambiguos assignment!
ambiguities.append(graph.variables[h]);
// print it out:
cout << "Found an ambiguous assignemnt to variable "
<< graph.variables[h] << "\n";
for (int k = 0; k < possibleAssignments.size() + 1; k++) {
float curProb = belief.get(k);
cout << curProb << " ";
}
cout << "\n";
}
}
}
int main( int argc, char *argv[] ) {
if ( argc != 3 ) {
cout << "Usage: " << argv[0] << " <filename.fg> [map|pd]" << endl << endl;
cout << "Reads factor graph <filename.fg> and runs" << endl;
cout << "map: Junction tree MAP" << endl;
cout << "pd : LBP and posterior decoding" << endl << endl;
return 1;
} else {
// Redirect cerr to inf.log
ofstream errlog("inf.log");
//streambuf* orig_cerr = cerr.rdbuf();
cerr.rdbuf(errlog.rdbuf());
// Read FactorGraph from the file specified by the first command line argument
FactorGraph fg;
fg.ReadFromFile(argv[1]);
// Set some constants
size_t maxiter = 10000;
Real tol = 1e-9;
size_t verb = 1;
// Store the constants in a PropertySet object
PropertySet opts;
opts.set("maxiter",maxiter); // Maximum number of iterations
opts.set("tol",tol); // Tolerance for convergence
opts.set("verbose",verb); // Verbosity (amount of output generated)
if (strcmp(argv[2], "map") == 0) {
// Construct another JTree (junction tree) object that is used to calculate
// the joint configuration of variables that has maximum probability (MAP state)
JTree jtmap( fg, opts("updates",string("HUGIN"))("inference",string("MAXPROD")) );
// Initialize junction tree algorithm
jtmap.init();
// Run junction tree algorithm
jtmap.run();
// Calculate joint state of all variables that has maximum probability
vector<size_t> jtmapstate = jtmap.findMaximum();
/*
// Report exact MAP variable marginals
cout << "Exact MAP variable marginals:" << endl;
for( size_t i = 0; i < fg.nrVars(); i++ )
cout << jtmap.belief(fg.var(i)) << endl;
*/
// Report exact MAP joint state
cerr << "Exact MAP state (log score = " << fg.logScore( jtmapstate ) << "):" << endl;
cout << fg.nrVars() << endl;
for( size_t i = 0; i < jtmapstate.size(); i++ )
cout << fg.var(i).label() << " " << jtmapstate[i] + 1 << endl; // +1 because in MATLAB assignments start at 1
} else if (strcmp(argv[2], "pd") == 0) {
// Construct a BP (belief propagation) object from the FactorGraph fg
// using the parameters specified by opts and two additional properties,
// specifying the type of updates the BP algorithm should perform and
// whether they should be done in the real or in the logdomain
BP bp(fg, opts("updates",string("SEQMAX"))("logdomain",true));
// Initialize belief propagation algorithm
bp.init();
// Run belief propagation algorithm
bp.run();
// Report variable marginals for fg, calculated by the belief propagation algorithm
cerr << "LBP posterior decoding (highest prob assignment in marginal):" << endl;
cout << fg.nrVars() << endl;
for( size_t i = 0; i < fg.nrVars(); i++ ) {// iterate over all variables in fg
//cout << bp.belief(fg.var(i)) << endl; // display the belief of bp for that variable
Factor marginal = bp.belief(fg.var(i));
Real maxprob = marginal.max();
for (size_t j = 0; j < marginal.nrStates(); j++) {
if (marginal[j] == maxprob) {
cout << fg.var(i).label() << " " << j + 1 << endl; // +1 because in MATLAB assignments start at 1
}
}
}
} else {
cerr << "Invalid inference algorithm specified." << endl;
return 1;
}
}
return 0;
}
