.. index:: GPAW
.. _GPAW:

GPAW
====

Description
-----------

GPAW is a density-functional theory (DFT) Python code based on the projector-augmented wave (PAW) method and the atomic simulation environment (ASE).

User instructions
-----------------

GPAW is available via the modules system.  To add it to your environment run:

.. code-block:: bash

    $ module load gpaw/1.2.0

This also sets the GPAW_SETUP_PATH environment variable to point to the 0.9.2 version of the gpaw set of atomic data files.

For usage instructions see the extensive `GPAW documentation <https://wiki.fysik.dtu.dk/gpaw/index.html>`_.

Source
------

https://wiki.fysik.dtu.dk/gpaw/install.html#getting-the-source-code

License
-------

GNU General Public License v3

Admin notes
-----------

First I modified customize.py to include the following::

    compiler = 'icc'
    libraries = ['mkl_intel_lp64', 'mkl_core', 'mkl_sequential', 'xc']

Then it was compiled and installed with:

.. code-block:: bash

    module load python/2.7.13 ase intel mkl openmpi libxc fftw
    python setup.py install --prefix=/common/debian/9.1/MPI/intel/2017.4/openmpi/2.1/gpaw/gpaw-1.2.0

Note this was done under the builder account on ramsay after first creating the
target directory and giving it ownership, which could be taken back once complete.
The atomic data files were downloaded with the following once the bare module
had been generated

.. code-block:: bash

   gpaw gpaw install-data /common/debian/9.1/MPI/intel/2017.4/openmpi/2.1/gpaw/gpaw-1.2.0/gpaw-setups

To get the environment variable to point to this directory the following was
set for the module template::

    cmth_std_module()
    prereq('ase', 'mkl', 'numpy', 'scipy', 'libxc', 'fftw')

    -- This is an unfortunately hacky way to set the gpaw-setups directory...
    local gpsdir = pathJoin(get_pkg_root(), 'gpaw-setups')
    local lfs = require("lfs")
    for filename in lfs.dir(gpsdir) do
        -- This cycles through the contents of this directory and saves the last item
        if filename ~= "." and filename ~= ".." then
            gpsetups = filename
        end
    end
    setenv('GPAW_SETUP_PATH', pathJoin(gpsdir, gpsetups))

This is maybe not the nicest way to do it, but given that any future installs
will most likely only have the most recent set of atomic data files there
shouldn't be any issue.