double cDirichletNode::entropy(){
double temp = 0;
double ent = -lngamma(a.sum(), temp);
for (int i=0; i < a.rows(); i++) {ent += lngamma(a(i), temp);}
ent += (a.sum() - a.rows())*psi(a.sum());
// ent -= (a - PVector::Ones(a.rows()))*psi();
for (int i=0; i < a.rows(); i++){ent -= (a(i) - 1)*psi(a(i));}
return ent;
}
double cGammaNode::calcBound(cBayesNet* net){
double bound = 0;
double temp = 0;
for (int i=0; i < lnE.rows(); i++) {
bound += pa*log(pb);
bound += (pa - 1.)*lnE(i);
bound -= pb*E1(i);
bound -= lngamma(pa, temp);
}
return bound + entropy();
}
double cGammaNode::entropy(){
double temp = 0;
double ent = 0;
for (int i=0; i < a.rows(); i++) {
ent += a(i);
ent -= log(b(i));
ent += lngamma(a(i), temp);
ent += (1. - a(i))*psi(a(i));
}
return ent;
}
double cDirichletNode::calcBound(cBayesNet* net){
double temp = 0;
double bound = ((a0 - PVector::Ones(a0.rows()))*lnE).sum() - lngamma(a0.sum(), temp);
for (int i=0; i < a0.rows(); i++) { bound += lngamma(a0(i), temp); }
return bound + entropy();
}