parmed.topologyobjects.DihedralType¶

class parmed.topologyobjects.DihedralType(phi_k, per, phase, scee=1.0, scnb=1.0, list=None)[source]¶

A dihedral type with a set of dihedral parameters

Parameters

phi_kfloat: The force constant in kcal/mol
perint: The dihedral periodicity
phasefloat: The dihedral phase in degrees
sceefloat, optional: 1-4 electrostatic scaling factor. Default is 1.0
scnbfloat, optional: 1-4 Lennard-Jones scaling factor. Default is 1.0
listTrackedList: A list of `DihedralType`s in which this is a member

Notes

Two DihedralType`s are equal if their `phi_k, per, phase, scee, and scnb attributes are equal

Examples

>>> dt1 = DihedralType(10.0, 2, 180.0, 1.2, 2.0)
>>> dt2 = DihedralType(10.0, 2, 180.0, 1.2, 2.0)
>>> dt1 is dt2
False
>>> dt1 == dt2
True
>>> dt1.idx # not part of any list or iterable
-1

As part of a list, they can be indexed

>>> dihedral_list = []
>>> dihedral_list.append(DihedralType(10.0, 2, 180.0, 1.2, 2.0,
...                                   list=dihedral_list))
>>> dihedral_list.append(DihedralType(10.0, 2, 180.0, 1.2, 2.0,
...                                   list=dihedral_list))
>>> dihedral_list[0].idx
0
>>> dihedral_list[1].idx
1

Attributes

idx
uphase
uphi_k

__init__(phi_k, per, phase, scee=1.0, scnb=1.0, list=None)[source]¶: DihedralType constructor

Methods

__init__(phi_k, per, phase[, scee, scnb, list])

DihedralType constructor

Attributes

`idx`
`uphase`
`uphi_k`