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Force Class Referenceabstract

Force objects apply forces to the particles in a System, or alter their behavior in other ways. More...

#include <Force.h>

+ Inheritance diagram for Force:

Public Member Functions

 Force ()
 
virtual ~Force ()
 
int getForceGroup () const
 Get the force group this Force belongs to.
 
void setForceGroup (int group)
 Set the force group this Force belongs to.
 

Protected Member Functions

virtual ForceImplcreateImpl () const =0
 When a Context is created, it invokes this method on each Force in the System.
 
ForceImplgetImplInContext (Context &context)
 Get the ForceImpl corresponding to this Force in a Context.
 
ContextImplgetContextImpl (Context &context)
 Get the ContextImpl corresponding to a Context.
 

Friends

class ContextImpl
 

Detailed Description

Force objects apply forces to the particles in a System, or alter their behavior in other ways.

This is an abstract class. Subclasses define particular forces.

More specifically, a Force object can do any or all of the following:

  • Add a contribution to the force on each particle
  • Add a contribution to the potential energy of the System
  • Modify the positions and velocities of particles at the start of each time step
  • Define parameters which are stored in the Context and can be modified by the user
  • Change the values of parameters defined by other Force objects at the start of each time step

Forces may be organized into "force groups". This is used for multiple time step integration, and allows subsets of the Forces in a System to be evaluated at different times. By default, all Forces are in group 0. Call setForceGroup() to change this. Some Force subclasses may provide additional methods to further split their computations into multiple groups. Be aware that particular Platforms may place restrictions on the use of force groups, such as requiring all nonbonded forces to be in the same group.

Constructor & Destructor Documentation

Force ( )
inline
virtual ~Force ( )
inlinevirtual

Member Function Documentation

virtual ForceImpl* createImpl ( ) const
protectedpure virtual

When a Context is created, it invokes this method on each Force in the System.

It should create a new ForceImpl object which can be used by the context for calculating forces. The ForceImpl will be deleted automatically when the Context is deleted.

Implemented in CustomGBForce, CustomHbondForce, CustomNonbondedForce, NonbondedForce, CustomCompoundBondForce, GBVIForce, CustomTorsionForce, CustomAngleForce, CustomBondForce, CustomExternalForce, GBSAOBCForce, CMAPTorsionForce, MonteCarloBarostat, RBTorsionForce, PeriodicTorsionForce, HarmonicAngleForce, AndersenThermostat, HarmonicBondForce, and CMMotionRemover.

ContextImpl& getContextImpl ( Context context)
protected

Get the ContextImpl corresponding to a Context.

int getForceGroup ( ) const

Get the force group this Force belongs to.

ForceImpl& getImplInContext ( Context context)
protected

Get the ForceImpl corresponding to this Force in a Context.

void setForceGroup ( int  group)

Set the force group this Force belongs to.

Parameters
groupthe group index. Legal values are between 0 and 31 (inclusive).

Friends And Related Function Documentation

friend class ContextImpl
friend

The documentation for this class was generated from the following file: