void
VarElim::absorveEvidence (void)
{
if (Globals::verbosity > 2) {
Util::printDashedLine();
cout << "(initial factor list)" << endl;
printActiveFactors();
}
const VarNodes& varNodes = fg.varNodes();
for (size_t i = 0; i < varNodes.size(); i++) {
if (varNodes[i]->hasEvidence()) {
if (Globals::verbosity > 1) {
cout << "-> aborving evidence on ";
cout << varNodes[i]->label() << " = " ;
cout << varNodes[i]->getEvidence() << endl;
}
const vector<size_t>& idxs =
varFactors_.find (varNodes[i]->varId())->second;
for (size_t j = 0; j < idxs.size(); j++) {
Factor* factor = factorList_[idxs[j]];
if (factor->nrArguments() == 1) {
factorList_[idxs[j]] = 0;
} else {
factorList_[idxs[j]]->absorveEvidence (
varNodes[i]->varId(), varNodes[i]->getEvidence());
}
}
}
}
}
void
VarElim::eliminate (VarId elimVar)
{
Factor* result = 0;
vector<size_t>& idxs = varFactors_.find (elimVar)->second;
for (size_t i = 0; i < idxs.size(); i++) {
size_t idx = idxs[i];
if (factorList_[idx]) {
if (result == 0) {
result = new Factor (*factorList_[idx]);
} else {
result->multiply (*factorList_[idx]);
}
delete factorList_[idx];
factorList_[idx] = 0;
}
}
totalFactorSize_ += result->size();
if (result->size() > largestFactorSize_) {
largestFactorSize_ = result->size();
}
if (result != 0 && result->nrArguments() != 1) {
result->sumOut (elimVar);
factorList_.push_back (result);
const VarIds& resultVarIds = result->arguments();
for (size_t i = 0; i < resultVarIds.size(); i++) {
vector<size_t>& idxs =
varFactors_.find (resultVarIds[i])->second;
idxs.push_back (factorList_.size() - 1);
}
}
}
