The CrystGap package provides functions for the computation with affine
crystallographic groups, in particular space groups. Also provided are
some functions dealing with related linear matrix groups, such as point
groups. For the definition of the standard crystallographic notions we
refer to the International Tables
Hah95, in particular the chapter
by Wondratschek Won95,
and to the introductory chapter in
Irreducible Maximal Finite Integral
Matrix Groups. The principal algorithms used in this package are
described in EGN97,
a preprint of which in included in the doc
directory of this package.
CrystGap is implemented in the GAP language,
and runs on any system
supporting GAP 3.4.4. The function
WyckoffLattice, however, requires
the share package XGap,
which in turn runs only under Unix. The
functions described in this chapter can be used only after loading
CrystGap with the command
gap> RequirePackage( "cryst" );
CrystGap has been developed by
Bettina Eick
Bettina.Eick@math.RWTH-Aachen.de
Franz Gähler
gaehler@pth.polytechnique.fr
Werner Nickel
werner@dcs.st-and.ac.uk
Please send bug reports, suggestions and other comments to any of these e-mail addresses.
The first and third authors acknowledge financial support from the Graduiertenkolleg it Analyse und Konstruktion in der Mathematik. The second author was supported by the Swiss Bundesamt fäur Bildung und Wissenschaft in the framework of the HCM programme of the European Community. This collaboration was in part made possible by financial support from the HCM project it Computational Group Theory.
GAP 3.4.4