Re: [ESPResSo-devel] Cellsystem, folded position, constraints

[Olaf Lenz]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: RIPEMD160

Ulf Schiller wrote:
> Another issue about constraints is whether they have periodic images.
> E.g. in case of walls, a common tutorial example is that one can
> simulate channel flow by putting a single wall into a system with
> periodic boundary conditions. This is not the case in ESPResSo. This
> might be a source of confusion (actually it was already).

This is, in fact, not very hard to solve: currently, the wall constraint
simply checks whether a particle is inside the wall, i.e. the distance
between particle and wall is negative, and it throws a background error,
if it is. Instead, one could simply give the constraint an option that
allows to symmetrize it, i.e. when the distance is negative, it simply
is negated.

Olaf
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.2 (GNU/Linux)
Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org

iD8DBQFGwHmdtQ3riQ3oo/oRA7tNAJ9C43LjwyT7SWNwZbbVPL8ECiS10QCdGOev
zso/qIg1OHIeGqeBot9QHBU=
=mFKW
-----END PGP SIGNATURE-----