import matplotlib.pyplot as plt
from tenpy.models import lattice
plt.figure(figsize=(6, 8))
ax = plt.gca()
lat = lattice.Triangular(4, 4, None, bc='periodic')
lat.plot_coupling(ax, linestyle='-', linewidth=3, label='nearest_neighbors')
for key, lw in zip(['next_nearest_neighbors',
                    'next_next_nearest_neighbors'],
                [1.5, 1.]):
    pairs = lat.pairs[key]
    lat.plot_coupling(ax, pairs, linestyle='--', linewidth=lw, color='gray', label=key)
lat.plot_sites(ax)
lat.plot_basis(ax, origin=-0.5*(lat.basis[0] + lat.basis[1]))
ax.set_aspect('equal')
ax.set_xlim(-1)
ax.set_ylim(-1)
ax.legend(loc='upper left')
plt.show()