Installation instructions

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Note that any of these installations also includes visclaw for plotting.

See also:

Install only PyClaw (serial)

If you wish to install just PyClaw, everything is handled by pip:

pip install clawpack

Next go to Running an example.

Install all Clawpack packages

First, download a tar file of the latest release:

See Clawpack components for a list of what’s included in this tar file.

Save this tar file in the directory where you want the top level of the clawpack tree to reside. Then untar using the command:

tar -xzvf clawpack-5.3.0.tar.gz

Then move into the top level directory:

cd clawpack-5.3.0

Next install the Python components of Clawpack:

python install

This will compile a lot of Fortran code using f2py and will produce a lot of output, so you might want to redirect the output, e.g.

python install > install_output.txt

If you get compilation errors in this step, you can still use the Classic, AMRClaw, and GeoClaw; see Install other packages without compiling PyClaw.

If you only plan to use PyClaw, jump to Running an example. If you plan to use Classic, AMRClaw, or GeoClaw continue with Set environment variables.

Set environment variables

To use the Fortran versions of Clawpack you will need to set the environment variable CLAW to point to the top level of clawpack tree (there is no need to perform this step if you will only use PyClaw). In the bash shell these can be set via:

export CLAW=/full/path/to/top/level

You also need to set FC to point to the desired Fortran compiler, e.g.:

export FC=gfortran   # or other preferred Fortran compiler

Consider putting the two commands above in a file that is executed every time you open a new shell or terminal window. On Linux machines with the bash shell this is generally the file .bashrc in your home directory. On a Mac it may be called .bash_profile.

If your environment variable CLAW is properly set, the command

ls $CLAW

should list the top level directory, and report for example:       riemann/        pyclaw/
amrclaw/        clawutil/
geoclaw/        visclaw/        classic/

Next go to Running an example.

Install other packages without compiling PyClaw

If you get errors in the compilation step when using pip install or python install, check Troubleshooting: Installation. If your problem is not addressed there, please let us know or raise an issue. You can still use the Fortran codes (AMRClaw, GeoClaw, and Classic) by doing the following.

First, download a tarfile of the latest release as described in Install all Clawpack packages.

Next Set environment variables. You must then also set your PYTHONPATH manually:


Then you should be able to do:

cd $CLAW   # assuming this environment variable was properly set
python symlink-only

This will create some symbolic links in the $CLAW/clawpack subdirectory of your top level Clawpack directory, but does not compile code or put anything in your site-packages. In Python you should now be able to do the following, for example:

>>> from clawpack import visclaw

If not then either your $PYTHONPATH environment variable is not set properly or the required symbolic links were not created.

Next go to Running an example.

Install only PyClaw (for running in parallel)

First, install PyClaw as explained above. Then see the install instructions for Running in parallel.

Alternatively, you may use the following shell scripts (assembled by Damian San Roman) to install everything:

Install the latest development version

The development version of Clawpack can be obtained by cloning This is advised for those who want to help develop Clawpack or to have the most recent bleeding edge version. See Installation instructions for developers for instructions.

Running Clawpack on a VM or in the Cloud

Virtual Machine. An alternative to installing the Installation Prerequisites and Clawpack itself is to use the Clawpack Virtual Machine.

Cloud Computing.

Installation Prerequisites

Operating system:

  • Linux

  • Mac OS X (you need to have the Xcode developer tools installed in order to have “make” working)

Much of Clawpack will work under Windows using Cygwin, but this is not officially supported.


See Fortran Compilers for more about which compilers work well with Clawpack. For Mac OSX, see for some installation options.


  • Python Version 2.7 or above (but not 3.0 or above, which is not backwards compatible)

  • NumPy (for PyClaw/VisClaw)

  • matplotlib (for PyClaw/VisClaw)

See Python Hints for information on installing the required modules and to get started using Python if you are not familiar with it.

Testing your installation


If you downloaded Clawpack manually, you can test your PyClaw installation as follows (starting from your clawpack directory):

cd pyclaw

This should return ‘OK’.


As a first test of the Fortran code, try the following:

cd $CLAW/classic/tests
make tests

This will run several tests and compare a few numbers from the solution with archived results. The tests should run in a few seconds.

There are similar tests subdirectories of $CLAW/amrclaw and $CLAW/geoclaw to do quick tests of these codes.

See also Testing your installation.