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AmoebaInPlaneAngleForce Class Reference

This class implements an interaction at trigonal centers corresponding to the projected in-plane angle bend energy between four particles. More...

#include <AmoebaInPlaneAngleForce.h>

+ Inheritance diagram for AmoebaInPlaneAngleForce:

Public Member Functions

 AmoebaInPlaneAngleForce ()
 Create an AmoebaAngleForce. More...
 
int getNumAngles () const
 Get the number of in-plane angle terms in the potential function. More...
 
void setAmoebaGlobalInPlaneAngleCubic (double cubicK)
 Set the global cubic term. More...
 
double getAmoebaGlobalInPlaneAngleCubic (void) const
 Get the global cubic term. More...
 
void setAmoebaGlobalInPlaneAngleQuartic (double quarticK)
 Set the global quartic term. More...
 
double getAmoebaGlobalInPlaneAngleQuartic (void) const
 Get the global quartic term. More...
 
void setAmoebaGlobalInPlaneAnglePentic (double penticK)
 Set the global pentic term. More...
 
double getAmoebaGlobalInPlaneAnglePentic (void) const
 Get the global pentic term. More...
 
void setAmoebaGlobalInPlaneAngleSextic (double sexticK)
 Set the global sextic term. More...
 
double getAmoebaGlobalInPlaneAngleSextic (void) const
 Get the global sextic term. More...
 
int addAngle (int particle1, int particle2, int particle3, int particle4, double length, double quadraticK)
 Add an angle term to the force field. More...
 
void getAngleParameters (int index, int &particle1, int &particle2, int &particle3, int &particle4, double &length, double &quadraticK) const
 Get the force field parameters for an angle term. More...
 
void setAngleParameters (int index, int particle1, int particle2, int particle3, int particle4, double length, double quadraticK)
 Set the force field parameters for an angle term. More...
 
void updateParametersInContext (Context &context)
 Update the per-angle parameters in a Context to match those stored in this Force object. More...
 
- Public Member Functions inherited from Force
 Force ()
 
virtual ~Force ()
 
int getForceGroup () const
 Get the force group this Force belongs to. More...
 
void setForceGroup (int group)
 Set the force group this Force belongs to. More...
 

Protected Member Functions

ForceImplcreateImpl () const
 When a Context is created, it invokes this method on each Force in the System. More...
 
- Protected Member Functions inherited from Force
ForceImplgetImplInContext (Context &context)
 Get the ForceImpl corresponding to this Force in a Context. More...
 
ContextImplgetContextImpl (Context &context)
 Get the ContextImpl corresponding to a Context. More...
 

Protected Attributes

double _globalCubicK
 
double _globalQuarticK
 
double _globalPenticK
 
double _globalSexticK
 

Detailed Description

This class implements an interaction at trigonal centers corresponding to the projected in-plane angle bend energy between four particles.

The interaction is defined by a 6th order polynomial in the angle between them. Only the quadratic term is set per-angle. The coefficients of the higher order terms each have a single value that is set globally.

To use it, create an AmoebaInPlaneAngleForce object then call addAngle() once for each angle. After an angle has been added, you can modify its force field parameters by calling setAngleParameters(). This will have no effect on Contexts that already exist unless you call updateParametersInContext().

Constructor & Destructor Documentation

Member Function Documentation

int addAngle ( int  particle1,
int  particle2,
int  particle3,
int  particle4,
double  length,
double  quadraticK 
)

Add an angle term to the force field.

Parameters
particle1the index of the first particle connected by the angle
particle2the index of the second particle connected by the angle
particle3the index of the third particle connected by the angle
particle4the index of the fourth particle connected by the angle
lengththe equilibrium angle, measured in radians
quadratick the quadratic force constant for the angle measured in kJ/mol/radian^2
Returns
the index of the angle that was added
ForceImpl* createImpl ( ) const
protectedvirtual

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.

Implements Force.

double getAmoebaGlobalInPlaneAngleCubic ( void  ) const

Get the global cubic term.

Returns
global cubicK term
double getAmoebaGlobalInPlaneAnglePentic ( void  ) const

Get the global pentic term.

Returns
global penticK term
double getAmoebaGlobalInPlaneAngleQuartic ( void  ) const

Get the global quartic term.

Returns
global quartic term
double getAmoebaGlobalInPlaneAngleSextic ( void  ) const

Get the global sextic term.

Returns
global sextic term
void getAngleParameters ( int  index,
int &  particle1,
int &  particle2,
int &  particle3,
int &  particle4,
double &  length,
double &  quadraticK 
) const

Get the force field parameters for an angle term.

Parameters
indexthe index of the angle for which to get parameters
particle1the index of the first particle connected by the angle
particle2the index of the second particle connected by the angle
particle3the index of the third particle connected by the angle
particle4the index of the fourth particle connected by the angle
lengththe equilibrium angle, measured in radians
quadratick the quadratic force constant for the angle measured in kJ/mol/radian^2
int getNumAngles ( ) const
inline

Get the number of in-plane angle terms in the potential function.

void setAmoebaGlobalInPlaneAngleCubic ( double  cubicK)

Set the global cubic term.

Parameters
cubicKthe cubic force constant for the angle
void setAmoebaGlobalInPlaneAnglePentic ( double  penticK)

Set the global pentic term.

Parameters
penticKthe pentic force constant for the angle
void setAmoebaGlobalInPlaneAngleQuartic ( double  quarticK)

Set the global quartic term.

Parameters
quarticKthe quartic force constant for the angle
void setAmoebaGlobalInPlaneAngleSextic ( double  sexticK)

Set the global sextic term.

Parameters
sexticKthe sextic force constant for the angle
void setAngleParameters ( int  index,
int  particle1,
int  particle2,
int  particle3,
int  particle4,
double  length,
double  quadraticK 
)

Set the force field parameters for an angle term.

Parameters
indexthe index of the angle for which to set parameters
particle1the index of the first particle connected by the angle
particle2the index of the second particle connected by the angle
particle3the index of the third particle connected by the angle
particle4the index of the fourth particle connected by the angle
lengththe equilibrium angle, measured in radians
quadratick the quadratic force constant for the angle, measured in kJ/mol/radian^2
void updateParametersInContext ( Context context)

Update the per-angle parameters in a Context to match those stored in this Force object.

This method provides an efficient method to update certain parameters in an existing Context without needing to reinitialize it. Simply call setAngleParameters() to modify this object's parameters, then call updateParametersInState() to copy them over to the Context.

The only information this method updates is the values of per-angle parameters. The set of particles involved in an angle cannot be changed, nor can new angles be added.

Member Data Documentation

double _globalCubicK
protected
double _globalPenticK
protected
double _globalQuarticK
protected
double _globalSexticK
protected

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