GitLab

simtk.openmm.app namespace to allow users to filter that warning out if they
want to.

force field utilizes nbfix functionality. Without this commit, using a ff14IPQ
topology file (or one modified by ParmEd to contain off-diagonal LJ elements),
would happily run, but ignore off-diagonal elements.

The new Chen and Garcia RNA force field (see doi:10.1073/pnas.1309392110) also
utilizes off-diagonal terms in its parametrization scheme.

One shortcoming is that the approach taken here -- using a pair parameter lookup
table -- cannot be currently used with a long-range correction because it is not
a `Continuous1DFunction' by virtue of using two `Discrete2DFunction'
TabulatedFunction classes.

Energies here match the values obtained with Amber to 0.01 -- 0.1 kcal/mol
(within 0.1% of the total).

pick up some bugs that were not caught in my initial test following the port
from ParmEd.

All 4 tests pass right now, although no periodic systems are being tested.
Currently CHARMM, XPLOR, and VMD tests are all being run (for the same ala-3
system).

Disable implicit solvent tests, since there is no robust radii assignment
routine yet (the radii are stored in the Amber topology file).  I will port my
assignment routine from ParmEd here shortly and then re-enable the GB tests.

Added unittest and 1 system tests. Includes 1 bugfix to resolving a circular import and 1 bugfix where dms wasn't creating the topology correctly when the water was specified in different chains