Clawpack

Jupyter notebooks

• An interactive notebook illustrating the Riemann solution for acoustics and shallow water equations can be viewed here. (Developed by Mauricio del Razo.)

• $AM586/codes/clawpack/acoustics_1d/acoustics_1d.ipynb contains a notebook Illustrating the acoustics equation with various boundary conditions. You can view it here.

• $AM586/codes/clawpack/advection_1d/advection_1d.ipynb contains a notebook Illustrating the advection equation with various methods. You can view it here.

  If you want to run these, you will have to be working on a computer with a recent version of Clawpack installed, along with a recent version of IPython and other Python tools, e.g. from the anaconda distribution.

Using SageMathCloud

See Using SageMathCloud for general information on using SMC. Some parts of Clawpack are installed on SMC by default, but only the PyClaw parts. For the notebook above, you need more of Clawpack. You can get it by following the instructions below.

To make Clawpack work in the notebook, you also have to create a file $HOME/.sagemathcloud-env that contains the lines:

export CLAW=$HOME/git/clawpack
export SAGE_PATH=$SAGE_PATH:$CLAW

You have to restart the project after creating this file the first time in order for this to take effect. (Click on Settings and then Restart.)

Note: Something is currently not working in the notebook above on SMC – when trying to plot the solution it hangs.

Installing Clawpack

If you want to install Clawpack, there are various approaches summarized in the documentation, but the easiest way to get the current version and keep it up to date is to get it from GitHub.

To put the clawpack directory in your home directory (change the last argument on the first line if you want it elsewhere):

git clone git://github.com/clawpack/clawpack.git  $HOME/clawpack
cd clawpack
python setup.py git-dev

Then set some environment variables (assuming you use the bash shell):

export CLAW=$HOME/clawpack            # or whereever you put it
export PYTHONPATH=$PYTHONPATH:$CLAW   # append to any existing path

(These export commands can be put in your .bashrc file or whatever script gets executed when you start a new shell, e.g. .bash_profile on a Mac.)

Then if you start Python or IPython, you should be able to do e.g.:

>>> import clawpack
>>> from clawpack.clawutil import nbtools

If the latter import statement doesn’t work, you might not have the latest version of Clawpack.