This directory contains links to the ScaFaCoS library which
is required to use the KSPACE scafacos and its kspace_style
scafacos command in a LAMMPS input script.

The ScaFaCoS library is available at http://scafacos.de or
on github at https://github.com/scafacos, the libary was
developed by a consortium of different universities in
Germany (Bonn, Chemnitz, Stuttgart, Wuppertal) and
the Research Centre Juelich (Juelich Supercomputing Centre).

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Instructions:

1.) Download ScaFaCoS at http://scafacos.de or directly from github
    https://github.com/scafacos where you can either clone the
    repository or download the latest stable release.
    NOTE: For the P2NFFT solver, you require an installation of the
          GNU Scientific Library (GSL). Also to ensure the correct
          linker-flags are used, ScaFaCoS employs the pkg-config
          tool, which is also required.
    If you cloned the repository, please refer to 2.), else continue
    with 3.)

2.) If you cloned the git repository, you require autotools to setup
    the library. For that the following packages are required:
      m4
      autotools
      automake
      libtools
    In the build_aux folder of the scafacos folder, you can find the
    get_autotools.sh script, that downloads and installs the tools
    to ${HOME}/local. To change the target folder, please change the
    value of 'myprefix' in that script.
    To start the auto-configuration process, please run the './bootstrap'
    command in the scafacos base-folder.

3.) If you downloaded the library as a tarball, please extract the file
    to somewhere in your file system, or if you finished running 
    './bootstrap', please run './configure' in the base folder.
    Important flags for './configure' are:
      --prefix=<install_dir>:       sets the directory the compiled files will
                                    be installed to [default: /usr/local]
      --fcs-enable-solvers=<list>:  sets the list of solvers that are going to
                                    be built. By default all solvers will be
                                    built. Currently supported by the kspace in LAMMPS
                                    are: direct, ewald, fmm, p2nfft
                                    The other solvers might work, but support
                                    is purely experimental at the moment. To
                                    give a list of solvers, use a comma seperated
                                    list.
      --fcs-disable-doc:            disables the compilation of the documentation,
                                    e.g. if no Latex is available on the system.

4.) To build the library after configuration, run 'make' from the base folder.

5.) To install the libray in the designated installation folder, run 'make install'.
    Installation is required, as ScaFaCoS does not support an in-source build!

6.) Create two soft links to this directory (lib/scafacos) to where the libary
    is installed. E.g. if you built ScaFaCoS in the default install directory:
      % ln -s /usr/local/include includelink
      % ln -s /usr/local/lib liblink
    for any custom directory <custom_dir>:
      % ln -s <custom_dir>/include includelink
      % ln -s <custom_dir>/lib liblink

7.) ScaFaCoS uses the pkg-config tool to supply the correct, so you need to setup your
    PKG_CONFIG_PATH environment variable to include the lib/pkgconfig folder in the
    installation directory.
    Depending on the shell you use, this can be done either by:
      % export PKG_CONFIG_PATH=<custom_dir>/lib/pkgconfig:${PKG_CONFIG_PATH}
    or
      % setenv PKG_CONFIG_PATH=<custom_dir>/lib/pkgconfig:${PKG_CONFIG_PATH}

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