-- one band on a square lattice
HTB = NewTightBinding()
HTB.Name = "square lattice"
HTB.Cell = {{1,0,0},{0,1,0},{0,0,1}}
HTB.Atoms = { {"A", {0,0,0}, {{"s", {"0"}}}} }
HTB.Hopping = { {"A.s","A.s",{ 1,0,0},{{-0.5}}}, {"A.s","A.s",{-1,0,0},{{-0.5}}},
                {"A.s","A.s",{0, 1,0},{{-0.5}}}, {"A.s","A.s",{0,-1,0},{{-0.5}}} }
kpath = { {"G",{0,0,0}}, 150, {"X",{pi,0,0}}, 150, {"M",{pi,pi,0}}, 200, {"G",{0,0,0}} }

-- a self-energy with two broad bands of poles between 1 and 2 and between -2 and -1
e, W = {0}, {}
for i = 1, 40 do
  e[#e+1] =  1 + (i-0.5)/40;  W[#W+1] = 0.015
  e[#e+1] = -1 - (i-0.5)/40;  W[#W+1] = 0.015
end
Sigma = ResponseFunction.New({e, W, mu=0, type="ListOfPoles"})

E = TightBinding.CalculateBands(HTB, kpath)
G = TightBinding.CalculateBands(HTB, kpath, Sigma)

Frame = {"Frame",{{"Ymin",-3},{"Ymax",3},{"dYTick",1},{"YLabel","Energy"}}}
Plots = {
  Lines     = Graphics.PlotBands(kpath, E, {Frame}),
  Broadened = Graphics.PlotBands(kpath, E, {Frame, {"GammaL",0.04}}),
  Sigma     = Graphics.PlotBands(kpath, G, {Frame, {"GammaL",0.04}}),
  Saturated = Graphics.PlotBands(kpath, G, {Frame, {"GammaL",0.04}, {"GammaG",0.06}, {"Saturation",3}, {"NPixelX",500}, {"NPixelY",400}}) }
for name, pl in pairs(Plots) do
  file = io.open("Bands"..name..".svg", "w")
  file:write(Graphics.ToSVG(pl, {{"RelativeSize",true}}))
  file:close()
end