How to use spglib example files
================================

This is the README file for spglib examples for C, Fortran, and
a linear tetrahedron method example. "tetrahedron_method.c" and
"tetrahedron_method.h" are distributed under kspclib
(https://github.com/atztogo/kspclib).

Examples of spglib functions in C
----------------------------------

To compile example.c::

   % gcc example.c -I[include directory] -L[library directory] -lsymspg -lm


Fortran wrapper
----------------

Fortran wrapper is required to use spglib from Fortran.

To complie example_f08.f90, please follow Makefile_f08::

   % make -f Makefile_f08

To compile obsolete example.f90::

   % gcc -c spglib_f.c
   % gfortran example.f90 spglib_f.o -L[library directory] -lsymspg -lm


Linear tetrahedron method
--------------------------

tetrahedron_method.c relies only kgrid.c and kgrid.h. Therefore in the
example in tetrahedron.c, although spg_get_ir_reciprocal_mesh is used
to obtain irreducible k-points, this is not essential for running
tetrahedorn method packed with the spglib distribution. To compile
tetrahedron.c::

   % gcc tetrahedron.c [source directory]/tetrahedron_method.c -I[include directory] -L[library directory] -lsymspg

tetrahedron.c is written to work with OpenMP. To compile with "-lgomp
-fopenmp", the tetrahedon method calculation is distributed into CPU
cores.

Atsushi Togo <atz.togo@gmail.com>