A tight-binding model on a square lattice
-----------------------------------------

Let us now consider free fermions on a Bravais lattice. 
We will set up a square lattice with the nearest
neighbour hopping using the ``BravaisLattice`` class of TRIQS, compute its
density of states (DOS) and then plot it by using again the ``oplot`` function.


.. plot:: userguide/python/ex1.py
    :scale: 70

More information on the lattice tools implemented in TRIQS can be found in the
:ref:`Python API <documentation>` (module :py:mod:`triqs.lattice`).