mc_weight_type Try() {
#ifdef DEBUG
std::cout << "I AM IN Try for Insert_Cdag_C_Delta" << std::endl;
std::cout << "CONFIG BEFORE: " << Config.DT << std::endl;
// for (int a = 0; a<Config.Na; ++a) print_det(Config.dets[a]);
#endif
// Pick up the value of alpha and choose the operators
const Hloc::Operator
& Op1(*Config.CdagOps[a_level][Random(Nalpha)]),
& Op2(*Config.COps[a_level][Random(Nalpha)]);
// Choice of times.
double tau1 = Random(Config.Beta), tau2 = Random(Config.Beta);
// record the length of the kinks
if (Config.RecordStatisticConfigurations) {
deltaTau = Config.CyclicOrientedTimeDistance(tau2 - tau1);
HISTO_Length_Kinks_Proposed<< deltaTau;
}
// Insert the operators Op1 and Op2
Configuration::OP_REF O1, O2;
tie (no_trivial_reject,O1,O2) = Config.DT.insertTwoOperators(tau1,Op1,tau2,Op2);
if (!no_trivial_reject) return 0;
// pick up the determinant
// NB ; the det has to be recomputed each time, since global moves will change it
det = Config.dets[a_level];
int numCdag=1;
// Find the position for insertion in the determinant
// NB : the determinant store the C in decreasing order.
for (Configuration::DET_TYPE::Cdagger_iterator p= det->Cdagger_begin();
(p != det->Cdagger_end()) && (p->tau > tau1) ; ++p, ++numCdag) {}
int numC=1;
for (Configuration::DET_TYPE::C_iterator p= det->C_begin();
(p != det->C_end()) && (p->tau > tau2) ; ++p, ++numC) {}
// acceptance probability
mc_weight_type p = Config.DT.ratioNewTrace_OldTrace() * det->try_insert(numCdag,numC,O1,O2);
double Tratio =power(2*Nalpha* Config.Beta / double(2*(det->NumberOfC()+1)), 2);
#ifdef DEBUG
std::cout << "Trace Ratio: " << Config.DT.ratioNewTrace_OldTrace() << std::endl;
std::cout << "p*T: " << p*Tratio << std::endl;
std::cout << "CONFIG AFTER: " << Config.DT << std::endl;
//for (int a = 0; a<Config.Na; ++a) print_det(Config.dets[a]);
#endif
return p*Tratio;
}
mc_weight_type Try() {
#ifdef DEBUG
std::cout << "I AM IN Try for Remove_Cdag_C_Delta" << std::endl;
std::cout << "CONFIG BEFORE: " << Config.DT << std::endl;
//for (int a = 0; a<Config.Na; ++a) print_det(Config.dets[a]);
#endif
// the det has to be recomputed each time, since global moves will change it
det = Config.dets[a_level];
// Pick up a couple of C, Cdagger to remove at random
const int Na(det->NumberOfC());
if (Na==0) return 0;
int numCdag = 1 + Random(Na);
int numC = 1 + Random(Na);
// det is in decreasing order.
numC = Na - numC + 1;
numCdag = Na - numCdag + 1;
// Remove the operators from the traces
// the -Na +1 is to move backward, to compare with V1 ...
Config.DT.removeTwoOperators(*det->select_Cdagger( numCdag ),
*det->select_C( numC ));
// Acceptance probability
mc_weight_type p = Config.DT.ratioNewTrace_OldTrace() * det->try_remove(numCdag,numC);
double Tratio = power(2*Nalpha* Config.Beta / double(2*Na) ,2);
#ifdef DEBUG
std::cout << "RATIO: " << Config.DT.ratioNewTrace_OldTrace() << std::endl;
std::cout << "CONFIG AFTER: " << Config.DT << std::endl;
//for (int a = 0; a<Config.Na; ++a) print_det(Config.dets[a]);
#endif
return p/Tratio;
}
