Package ffx.algorithms.dynamics.integrators

Class BetterBeeman

java.lang.Object

ffx.algorithms.dynamics.integrators.Integrator

ffx.algorithms.dynamics.integrators.BetterBeeman

public class BetterBeeman
extends Integrator

Integrate Newton's equations of motion using a Beeman multistep recursion formula; the actual coefficients are Brooks' "Better Beeman" values.

Since:

1.0

Author:

Michael J. Schnieders

Field Summary

Fields inherited from class ffx.algorithms.dynamics.integrators.Integrator

constraints, constraintTolerance, dt, state, useConstraints

Constructor Summary

Constructors

Constructor	Description
BetterBeeman(SystemState state)	Constructor for BetterBeeman.

Method Summary

Modifier and Type	Method	Description
void	postForce(double[] gradient)	Integrator post-force evaluation operation.
void	preForce(Potential potential)	Integrator pre-force evaluation operation.
void	setTimeStep(double dt)	Set the time step.
String	toString()

Methods inherited from class ffx.algorithms.dynamics.integrators.Integrator

addConstraints, copyAccelerationToPrevious, getConstraints, getTimeStep, parseIntegrator

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Details

BetterBeeman

public BetterBeeman(SystemState state)

Constructor for BetterBeeman.

Parameters:

state - The current state of the molecular dynamics simulation to operate on.

Method Details

postForce

public void postForce(double[] gradient)

Integrator post-force evaluation operation.

Use Newton's second law to get the next acceleration and find the full-step velocities using the Beeman recursion.

Specified by:

postForce in class Integrator

Parameters:

gradient - the gradient for the post-force operation.

preForce

public void preForce(Potential potential)

Integrator pre-force evaluation operation.

Store the current atom positions, then find new atom positions and half-step velocities via Beeman recursion.

Specified by:

preForce in class Integrator

Parameters:

potential - the Potential this integrator operates on.

setTimeStep

public void setTimeStep(double dt)

Set the time step.

Specified by:

setTimeStep in class Integrator

Parameters:

dt - the time step (psec).

toString

public String toString()

Overrides:

toString in class Object