-------
Riemann
-------

The Riemann module is a simple code generator for hyperbolic problems in the
style of `CLAWPACK`.  Given either the flux (f) or the jacobian (A) of a
hyperbolic equation as below:


.. math::

    q_t + f(q)*q_t = 0

    q_t + A*q_t = 0

Currently only 1D simple kernels are implemented.

Using Riemann Generator
-----------------------

First you define your equation, for example an acoustic equation:

.. code-block:: python

    from ignition.riemann import *

    q = Conserved('q')
    p, u = q.fields(['p','u'])
    rho = Constant('rho')
    K = Constant('bulk')

    f = [ K*u ,
          p/rho]

We pass this code to the generator:

.. code-block:: python

    generate(flux=f, conserved=q, filename="acoustics_kernel.py")

For the full example see ``demo/riemann``.

.. CLAWPACK: http://clawpack.org/