Verylong operator* (const Verylong &u, const Verylong &v)
{
Verylong pprod("1"), tempsum("0");
for (int j=0; j<v.vlen; j++)
{
int digit = v.vlstr[j] - '0';
pprod = u.multdigit(digit);
pprod = pprod.mult10(j);
tempsum += pprod;
}
tempsum.vlsign = u.vlsign ^ v.vlsign;
return tempsum;
}
void MomentumCorrFunc::correlateFrames(int frame1, int frame2) {
SimInfo::MoleculeIterator mi1;
SimInfo::MoleculeIterator mi2;
Molecule* mol1;
Molecule* mol2;
Molecule::AtomIterator ai1;
Molecule::AtomIterator ai2;
Atom* atom1;
Atom* atom2;
std::vector<Vector3d> atomPositions1;
std::vector<Vector3d> atomPositions2;
std::vector<Vector3d> atomVelocity1;
std::vector<Vector3d> atomVelocity2;
int thisAtom1, thisAtom2;
Snapshot* snapshot1 = bsMan_->getSnapshot(frame1);
Snapshot* snapshot2 = bsMan_->getSnapshot(frame2);
assert(snapshot1 && snapshot2);
RealType time1 = snapshot1->getTime();
RealType time2 = snapshot2->getTime();
int timeBin = int ((time2 - time1) /deltaTime_ + 0.5);
updateFrame(frame1);
atomPositions1.clear();
for (mol1 = info_->beginMolecule(mi1); mol1 != NULL;
mol1 = info_->nextMolecule(mi1)) {
for(atom1 = mol1->beginAtom(ai1); atom1 != NULL;
atom1 = mol1->nextAtom(ai1)) {
atomPositions1.push_back(atom1->getPos(frame1));
atomVelocity1.push_back(atom1->getVel(frame1));
}
}
updateFrame(frame2);
atomPositions2.clear();
for (mol2 = info_->beginMolecule(mi2); mol2 != NULL;
mol2 = info_->nextMolecule(mi2)) {
for(atom2 = mol2->beginAtom(ai2); atom2 != NULL;
atom2 = mol2->nextAtom(ai2)) {
atomPositions2.push_back(atom2->getPos(frame2));
atomVelocity2.push_back(atom2->getVel(frame2));
}
}
thisAtom1 = 0;
for (mol1 = info_->beginMolecule(mi1); mol1 != NULL;
mol1 = info_->nextMolecule(mi1)) {
for(atom1 = mol1->beginAtom(ai1); atom1 != NULL;
atom1 = mol1->nextAtom(ai1)) {
Vector3d r1 = atomPositions1[thisAtom1];
Vector3d p1 = atom1->getMass() * atomVelocity1[thisAtom1];
thisAtom2 = 0;
for (mol2 = info_->beginMolecule(mi2); mol2 != NULL;
mol2 = info_->nextMolecule(mi2)) {
for(atom2 = mol2->beginAtom(ai2); atom2 != NULL;
atom2 = mol2->nextAtom(ai2)) {
Vector3d r2 = atomPositions2[thisAtom2];
Vector3d p2 = atom2->getMass() * atomVelocity1[thisAtom1];
Vector3d deltaPos = (r2-r1);
Vector3d dp2( deltaPos.x() * deltaPos.x(),
deltaPos.y() * deltaPos.y(),
deltaPos.z() * deltaPos.z());
Vector3d pprod( p1.x() * p2.x(),
p1.y() * p2.y(),
p1.z() * p2.z());
histogram_[timeBin] += outProduct(dp2, pprod);
thisAtom2++;
}
}
thisAtom1++;
}
}
count_[timeBin]++;
}
