OutOfPlaneSite¶

class openmm.openmm.OutOfPlaneSite(*args)¶

This is a VirtualSite that computes the particle location based on three other particles’ locations. If r₁ is the location of particle 1, r₁₂ is the vector from particle 1 to particle 2, and r₁₃ is the vector from particle 1 to particle 3, then the virtual site location is given by

r₁ + w₁₂r₁₂ + w₁₃r₁₃ + w_cross(r₁₂ x r₁₃)

The three weight factors are user-specified. This allows the virtual site location to be out of the plane of the three particles. Note that while w₁₂ and w₁₃ are unitless, w_cross has units of inverse distance.

__init__(self, particle1, particle2, particle3, weight12, weight13, weightCross) → OutOfPlaneSite ¶

__init__(self, other) → OutOfPlaneSite

Create a new OutOfPlaneSite virtual site.

Parameters

particle1 (int) – the index of the first particle
particle2 (int) – the index of the second particle
particle3 (int) – the index of the third particle
weight12 (double) – the weight factor for the vector from particle1 to particle2
weight13 (double) – the weight factor for the vector from particle1 to particle3
weightCross (double) – the weight factor for the cross product

Methods

`__init__`(-> OutOfPlaneSite)	Create a new OutOfPlaneSite virtual site.
`getNumParticles`(self)	Get the number of particles this virtual site depends on.
`getParticle`(self, particle)	Get the index of a particle this virtual site depends on.
`getWeight12`(self)	Get the weight factor for the vector from particle1 to particle2.
`getWeight13`(self)	Get the weight factor for the vector from particle1 to particle3.
`getWeightCross`(self)	Get the weight factor for the cross product.

Attributes

thisown

The membership flag

property thisown¶: The membership flag

getWeight12(self) → double¶: Get the weight factor for the vector from particle1 to particle2.

getWeight13(self) → double¶: Get the weight factor for the vector from particle1 to particle3.

getWeightCross(self) → double¶: Get the weight factor for the cross product.

getNumParticles(self) → int¶: Get the number of particles this virtual site depends on.

getParticle(self, particle) → int¶

Get the index of a particle this virtual site depends on.

Parameters: particle (int) – the particle to get (between 0 and getNumParticles())
Returns: the index of the particle in the System
Return type: int