void
OPOrientationalOrder::ticker()
{
size_t count(0);
ComplexNum sum(0,0);
BOOST_FOREACH(const Particle& part, Sim->particleList)
{
Neighbours nbs;
static_cast<const GNeighbourList*>
(Sim->dynamics.getGlobals()[_nblistID].get())
->getParticleNeighbourhood
(part, magnet::function::MakeDelegate
(&nbs, &Neighbours::addNeighbour));
if (nbs._neighbours.size() >= 6)
{
std::vector<MagVec> bonds;
BOOST_FOREACH(const size_t& id2, nbs._neighbours)
{
Vector bond = Sim->particleList[id2].getPosition() - part.getPosition();
Sim->dynamics.BCs().applyBC(bond);
bonds.push_back(bond);
}
std::sort(bonds.begin(), bonds.end());
if (bonds.size() > 6)
bonds.erase(bonds.begin()+6, bonds.end());
//Normalise the vectors.
BOOST_FOREACH(MagVec& vec, bonds)
{
vec /= vec.nrm();
double angle;
if (vec[0] != 0)
angle = atan(vec[1]/vec[0]);
else
if (vec[1] > 0)
angle = M_PI / 2;
else
angle = - M_PI / 2;
if (vec[0] < 0) angle += M_PI;
sum += std::exp(ComplexNum(0, 6 * angle));
}
++count;
}
ComplexNum operator/ (ComplexNum a, ComplexNum b)
{
ComplexNum temp = a * ComplexNumUtils::Conjugate(b);
float bNormSq = b.GetReal() * b.GetReal() + b.GetImaginary() * b.GetImaginary();
return ComplexNum(temp.GetReal() / bNormSq, temp.GetImaginary() / bNormSq);
}
ComplexNum operator* (ComplexNum a, ComplexNum b)
{
return ComplexNum((a.GetReal() * b.GetReal() - a.GetImaginary() * b.GetImaginary()), (a.GetReal() * b.GetImaginary() + a.GetImaginary() * b.GetReal()));
}
