void ReadHoppingsSection()
{
if (tb.hoppings != null)
ThrowEx("Multiple hoppings sections found.");
if (LineType != LineType.NewSubSection)
ThrowEx("Hoppings section must start with :..: delimited section.");
tb.hoppings = new HoppingPairList();
while (!EOF && LineType != LineType.NewSection)
{
string[] values = ReadSubSectionParameters();
int left = int.Parse(values[0]) - 1;
int right = int.Parse(values[1]) - 1;
HoppingPair p = new HoppingPair(left, right);
tb.hoppings.Add(p);
//Output.WriteLine("Reading hoppings for {0}-{1}", left + 1, right + 1);
ReadNextLine();
while (LineType == LineType.Hopping || LineType == LineType.Numeric)
{
List<string> vals = new List<string>();
vals.AddRange(Line.Replace('\t', ' ').Split(new char[] { ' ' }, StringSplitOptions.RemoveEmptyEntries));
if (vals[0] == "T=") vals.RemoveAt(0);
if (vals[3] == "hop=") vals.RemoveAt(3);
double value = double.Parse(vals[vals.Count - 1]);
Vector3 loc = new Vector3(double.Parse(vals[0]), double.Parse(vals[1]), double.Parse(vals[2]));
HoppingValue v = new HoppingValue();
v.Value = value;
v.R = loc;
p.Hoppings.Add(v);
ReadNextLine();
}
//Output.WriteLine("Count: {0}", p.Hoppings.Count);
}
}
void ApplySymmetries()
{
List<Matrix> validSyms = new List<Matrix>();
Matrix reduce = new Matrix(3, 3);
reduce.SetRows(tb.lattice.G1, tb.lattice.G2, tb.lattice.G3);
int symIndex = 0;
using (StreamWriter s = new StreamWriter("syms"))
{
foreach (var sym in GetPossibleSymmetries())
{
symIndex++;
s.WriteLine();
s.WriteLine("Applying symmetry " + symIndex.ToString() + ":");
s.WriteLine(sym);
Matrix lat = new Matrix(3, 3);
lat.SetColumns(sym * tb.lattice.A1, sym * tb.lattice.A2, sym * tb.lattice.A3);
lat = reduce * lat;
s.WriteLine("Lattice vector test...");
if (CheckLatticeSymmetry(lat) == false)
goto fail;
Dictionary<int, int> sitemap = new Dictionary<int, int>();
s.WriteLine("Generating site map...");
for (int i = 0; i < tb.sites.Count; i++)
{
var site = tb.sites[i];
Vector3 loc = sym * site.Location;
int index = tb.Orbitals.FindIndex(tb.lattice, loc);
if (index == -1)
{
s.WriteLine("Failed to map site " + i.ToString());
goto fail;
}
sitemap[i] = index;
s.WriteLine(" " + i.ToString() + " => " + index.ToString());
}
HoppingPairList newHops = new HoppingPairList();
// rotate hoppings
for (int i = 0; i < tb.hoppings.Count; i++)
{
var pair = tb.hoppings[i];
int newleft = sitemap[pair.Left];
int newright = sitemap[pair.Right];
HoppingPair newPair = new HoppingPair(newleft, newright);
newHops.Add(newPair);
foreach (var hop in pair.Hoppings)
{
HoppingValue v = new HoppingValue();
v.Value = hop.Value;
v.R = sym * hop.R;
newPair.Hoppings.Add(v);
}
}
s.WriteLine("Performing hopping test...");
if (newHops.Equals(tb.hoppings) == false)
goto fail;
s.WriteLine("Success.");
validSyms.Add(sym);
continue;
fail:
s.WriteLine("Failed.");
}
// now apply symmetries to reduce k-points in kmesh
int initialKptCount = tb.kmesh.Kpts.Count;
System.Diagnostics.Stopwatch watch = new System.Diagnostics.Stopwatch();
watch.Start();
foreach (var sym in validSyms)
{
for (int i = 0; i < tb.kmesh.Kpts.Count; i++)
{
KPoint kpt = tb.kmesh.Kpts[i];
Vector3 trans = kpt.Value;
/*
for (int j = 0; j < 3; j++)
{
trans = sym * trans;
int index = kmesh.IndexOf(trans, i+1);
if (index == -1)
continue;
kmesh.Kpts.RemoveAt(index);
kpt.Weight ++;
}
*/
}
}
watch.Stop();
string fmt = string.Format("{0} total kpts, {1} irreducible kpts. Applying symmetries took {2} seconds.",
initialKptCount, tb.kmesh.Kpts.Count, watch.ElapsedMilliseconds / 1000);
Output.WriteLine(fmt);
s.WriteLine(fmt);
}
}
