The Open Forcefield Toolkit provides implementations of the SMIRNOFF format, parameterization engine, and other tools. Documentation available at http://open-forcefield-toolkit.readthedocs.io
In #1861 while disallowing SMIRKS-based lookups I also removed support for int-based indexing into the parameter list, which I don't think should be considered unsafe.
In [1]: from openff.toolkit import ForceField
In [2]: ForceField("opc.offxml")['VirtualSites'].parameters[0]
/Users/mattthompson/micromamba/envs/openff-interchange-env/lib/python3.11/site-packages/smirnoff99frosst/smirnoff99frosst.py:11: UserWarning: Module openff was already imported from None, but /Users/mattthompson/software/openff-interchange is being added to sys.path
from pkg_resources import resource_filename
---------------------------------------------------------------------------
NotImplementedError Traceback (most recent call last)
Cell In[2], line 1
----> 1 ForceField("opc.offxml")['VirtualSites'].parameters[0]
File ~/micromamba/envs/openff-interchange-env/lib/python3.11/site-packages/openff/toolkit/typing/engines/smirnoff/parameters.py:1614, in VirtualSiteParameterList.__getitem__(self, val)
1613 def __getitem__(self, val):
-> 1614 raise NotImplementedError(
1615 "VirtualSiteHandler does not support __getitem__ lookups due to the "
1616 "number of values required to uniquely identify a specific parameter."
1617 )
NotImplementedError: VirtualSiteHandler does not support __getitem__ lookups due to the number of values required to uniquely identify a specific parameter.
mattwthompson
commented
4 months ago
In #1861 while disallowing SMIRKS-based lookups I also removed support for int-based indexing into the parameter list, which I don't think should be considered unsafe.