[MMTK] MMTK 2.1.2
Konrad Hinsen
hinsen@cnrs-orleans.fr
Mon, 7 Aug 2000 16:18:47 +0200
It has been a while since the last MMTK release, and although there
are no ground-breaking new features, the bug fixes and performance
optimizations might well be interesting for some users, so I decided
to publish a new development release, MMTK 2.1.2, available immediately
at
ftp://dirac.cnrs-orleans.fr/pub/MMTK/
There is also a new release of ScientificPython, version 2.1.3, available
from
ftp://dirac.cnrs-orleans.fr/pub/ScientificPython/
MMTK 2.1.2 does not require an update of ScientificPython, except for
profiting from the new features in the TrajectoryViewer tool.
The following excerpt from the change log summarizes the evolution
since the last stable release, MMTK 2.0:
---------------------------------------------------------------------------
2.1.1 --> 2.1.2
===============
New features:
- The TrajectoryViewer tool (in Tools/TrajectoryViewer) was extended
by normal mode projections for proteins.
- The structure of trajectory files can be influenced by specifying
a "block size", which can be used to optimize I/O performance on
very large files.
- Reading of single-atom and rigid-body trajectories has been
optimized.
Bug fixes:
- The functions MMTK.Biopolymers.defineAminoAcidResidue and
MMTK.Biopolymers.defineNucleicAcidResidue didn't work.
- The method MMTK.Collection.GroupOfAtoms.findTransformationAsQuaternion
returned randomly one of the two equivalent quaternions that desribe
the rigid-body rotation. This doesn't matter for most purposes, but
it creates non-continuous quaternion trajectories when applied to a
sequence of configurations. The method has been changed to return
the quaternion that has a positive real part.
- Rigid-body trajectories (in module Trajectory) were wrong in certain
circumstances.
2.1.0 --> 2.1.1
===============
Modifications:
- Improved load balance for shared memory parallelization.
- The united-atom models for amino acids were changed from Amber 91
conventions to OPLS by removing the fake "lone pair" atoms.
Note that there was never proper support for lone pair atoms, so
this model wasn't functional, and therefore nothing should be
broken by this change. Now the united-atom model is actually
fully usable together with the OPLS force field.
(Thanks to Krzysztof Murzyn for fixing this!)
Additions:
- Basic MPI support. Only energy evaluation has been parallelized,
using a data-replication approach. All processors execute the same
code and cooperate only during energy evaluation. See
the Example MPI/md.py for more information.
- New force fields: HarmonicForceField, CalphaForceField, SPCEForceField.
The first two are designed for proteins, the last one is only for
water.
2.0 --> 2.1.0
=============
Bug fixes:
- Addition of force fields didn't work when one of the terms was
already a compound force field.
- Memory allocation bug in DCD output.
- Restarting NPT dynamics simulations didn't work due to a reported
universe mismatch. This was caused by the different box size.
- MMTK.DCD.writeDCDPDB produced a PDB file with non-contiguous molecules for
periodic universes.
- In the electrostatic options for the Amber force field, the "screened"
option was misinterpreted as "ewald".
Modifications:
- The method objectList() for collections and universes now takes
an optional argument specifying a class; only the objects corresponding
to this class are returned. This permits a simple identification of
proteins etc.
- The universe description that is stored in a trajectory now contains
the force field and environment objects (thermostats and barostats).
- Optional name argument for C evaluator objects for bonded
interactions.
Additions:
- Thread support.
- Module MMTK.ForceFields.Restraints.
- New function MMTK.DCD.writeVelocityDCDPDB for exporting velocities
to velocity DCD files.
- New method pairIndices for nonbonded list objects.
---------------------------------------------------------------------------
As always, I am interested in all the feedback you can provide.
Konrad.
--
-------------------------------------------------------------------------------
Konrad Hinsen | E-Mail: hinsen@cnrs-orleans.fr
Centre de Biophysique Moleculaire (CNRS) | Tel.: +33-2.38.25.55.69
Rue Charles Sadron | Fax: +33-2.38.63.15.17
45071 Orleans Cedex 2 | Deutsch/Esperanto/English/
France | Nederlands/Francais
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