QFunctionsDiscrete
PerseusBGPlanner::BackupStageAll(const BeliefSet &S,
const QFunctionsDiscrete &Q) const
{
vector<double> VB=BeliefValue::GetValues(S,Q),
VBalpha;
int nrB=VB.size(),
nrS=GetPU()->GetNrStates();
QFunctionsDiscrete Q1(Q.size());
AlphaVector alpha(nrS);
ValueFunctionPOMDPDiscrete V=QFunctionsToValueFunction(Q);
GaoVectorSet Gao=BackupStageLeadIn(V);
ValueFunctionPOMDPDiscrete Qalphas;
for(int k=0;k<nrB;++k)
{
Qalphas.clear();
for(unsigned int a=0;a!=GetPU()->GetNrJointActions();++a)
{
// backup the belief
alpha=BeliefBackup(*S[k],a,Gao,V,_m_backupType);
// add alpha to Q1
if(!VectorIsInValueFunction(alpha,Q1[a]))
Q1[a].push_back(alpha);
Qalphas.push_back(alpha);
}
if(GetVerbose())
{
VBalpha=BeliefValue::GetValues(S,Qalphas);
cout << "Added vectors for " << k << " (V " << VBalpha[k]
<< ")" << endl;
}
}
BackupStageLeadOut(Gao);
return(Q1);
}
void MonahanPOMDPPlanner::MonahanCrossSum(const GaoVectorSet &G,
QFunctionsDiscrete &Q,
Index a,
bool doIncPrune,
size_t maxNrAlphas) const
{
Index nrS=GetPU()->GetNrStates(),
nrO=GetPU()->GetNrJointObservations();
AlphaVector alpha(nrS);
#if DEBUG_AlphaVectorPlanning_CrossSum
cout << "AlphaVectorPlanning::MonahanCrossSum for action " << a << endl;
#endif
// initialize with the number of vectors already computed for other time steps
size_t nrVectorsComputed=GetNrVectors();
// Do the cross-sums, creates G_a of (3.25)
VectorSet Ga=*G[a][0];
for(Index o=1; o!=nrO; o++)
{
if(doIncPrune)
{
VectorSet Ga2=CrossSum(Ga,*G[a][o]);
#if 0
VectorSet Ga1=Prune(Ga2,maxNrAlphas);
Ga=Ga1;
#else
Ga=Prune(Ga2);
#endif
}
else
{
VectorSet Ga1=CrossSum(Ga,*G[a][o]);
Ga=Ga1;
}
#if DEBUG_AlphaVectorPlanning_CrossSum
if(maxNrAlphas)
cout << "AlphaVectorPlanning::MonahanCrossSum nrAlphas " << Ga.size1()
<< " (max " << maxNrAlphas << ")" << endl;
#endif
CheckMaxNrVectors(maxNrAlphas,nrVectorsComputed+Ga.size1());
}
// Add the resulting vectors to V (HV_n of (3.25))
for(Index k=0; k!=Ga.size1(); ++k)
{
alpha.SetAction(a);
for(Index s=0; s!=nrS; s++)
alpha.SetValue(Ga(k,s),s);
Q[a].push_back(alpha);
nrVectorsComputed++;
}
if(!doIncPrune)
{
Q[a]=Prune(Q[a]);
CheckMaxNrVectors(maxNrAlphas,nrVectorsComputed+Q[a].size());
// THIS IS WRONG
throw(E("MonahanPOMDPPlanner fix error"));
if(maxNrAlphas && Q.size()>maxNrAlphas)
{
stringstream ss;
ss << "AlphaVectorPlanning::MonahanCrossSum() too many alpha vectors "
<< Q.size() << ">" << maxNrAlphas;
throw(E(ss.str()));
}
}
}
QFunctionsDiscrete
PerseusBGPlanner::BackupStageSamplingAlt(const BeliefSet &S,
const QFunctionsDiscrete &Q) const
{
vector<double> VB=BeliefValue::GetValues(S,Q),
VBalpha;
int nrB=VB.size(),
nrNotImproved=nrB,
nrS=GetPU()->GetNrStates(),
k;
vector<bool> stillNeedToBeImproved(nrB,true);
QFunctionsDiscrete Q1(Q.size());
AlphaVector alpha(nrS);
ValueFunctionPOMDPDiscrete V=QFunctionsToValueFunction(Q);
GaoVectorSet Gao=BackupStageLeadIn(V);
ValueFunctionPOMDPDiscrete Qalphas;
k=-1;
while(nrNotImproved!=0)
{
Qalphas.clear();
for(unsigned int a=0;a!=GetPU()->GetNrJointActions();++a)
{
// sample a belief index from the number of not improved beliefs
k=SampleNotImprovedBeliefIndex(stillNeedToBeImproved,nrNotImproved);
// backup the belief
alpha=BeliefBackup(*S[k],a,Gao,V,_m_backupType);
// check whether alpha improves the value of S[k]
double x=S[k]->InnerProduct(alpha.GetValues());
// if not, get copy from old value function
if(x<VB[k]) //QB[a][k])//VB[k])
{
#if DEBUG_PerseusBGPlanner
cout << "Getting n-1 vector for action " << a << ", belief "
<< k << " (" << x << " < " << VB[k] << ")" << endl;
#endif
alpha=BeliefValue::GetMaximizingVector(S,k,Q[a]);
}
else
{
if(GetVerbose())
cout << "Added vector for action " << a << ", belief "
<< k << " (Q " << x << " >= " << VB[k] << ")"
<< endl;
}
// add alpha to Q1
if(!VectorIsInValueFunction(alpha,Q1[a]))
Q1[a].push_back(alpha);
Qalphas.push_back(alpha);
}
// update which beliefs have been improved
VBalpha=BeliefValue::GetValues(S,Qalphas);
int nrImprovedByAlpha=0;
for(int b=0;b!=nrB;b++)
if(stillNeedToBeImproved[b] && VBalpha[b]>=VB[b])
{
stillNeedToBeImproved[b]=false;
nrNotImproved--;
nrImprovedByAlpha++;
}
if(GetVerbose())
cout << "Added vectors for " << k << " (V " << VBalpha[k]
<< " improved " << nrImprovedByAlpha << ")" << endl;
}
BackupStageLeadOut(Gao);
return(Q1);
}