sc::FinDispMolecularGradient Class Reference

Computes the molecular gradient by finite differences of energies. More...

#include <chemistry/molecule/findisp.h>

Inheritance diagram for sc::FinDispMolecularGradient:

Public Member Functions
	FinDispMolecularGradient (const Ref< MolecularEnergy > &)
	FinDispMolecularGradient (const Ref< KeyVal > &)
	The FinDispMolecularGradient KeyVal constructor is used to generate a FinDispMolecularGradient object from the input. More...
	FinDispMolecularGradient (StateIn &)
void	save_data_state (StateOut &)
	Save the base classes (with save_data_state) and the members in the same order that the StateIn CTOR initializes them. More...
RefSCVector	cartesian_gradient ()
	This returns the cartesian gradient. More...
void	set_checkpoint (int c)
	Set checkpoint option.
int	checkpoint () const
	Return the current value of the checkpoint option.
void	set_energy (const Ref< MolecularEnergy > &energy)
	Some MolecularGradient specializations require a molecular energy object. More...
MolecularEnergy *	energy () const
	This returns a MolecularEnergy object, if used by this specialization. More...
Ref< SCMatrixKit >	matrixkit () const
RefSCDimension	d3natom () const
void	set_desired_accuracy (double acc)
	Sets the desired accuracy. More...
void	set_eliminate_quadratic_terms (bool e)
void	set_disp_size (double s)
Public Member Functions inherited from sc::MolecularGradient
	MolecularGradient (const Ref< KeyVal > &)
	The MolecularGradient KeyVal constructor is used to generate a MolecularGradient object from the input. More...
	MolecularGradient (StateIn &)
RefSCDimension	d3natom ()
Ref< SCMatrixKit >	matrixkit () const
virtual double	desired_accuracy () const
	Reports the desired accuracy. More...
Public Member Functions inherited from sc::SavableState
SavableState &	operator= (const SavableState &)
void	save_state (StateOut &)
	Save the state of the object as specified by the StateOut object. More...
void	save_object_state (StateOut &)
	This can be used for saving state when the exact type of the object is known for both the save and the restore. More...
virtual void	save_vbase_state (StateOut &)
	Save the virtual bases for the object. More...
Public Member Functions inherited from sc::DescribedClass
	DescribedClass (const DescribedClass &)
DescribedClass &	operator= (const DescribedClass &)
ClassDesc *	class_desc () const MPQC__NOEXCEPT
	This returns the unique pointer to the ClassDesc corresponding to the given type_info object. More...
const char *	class_name () const
	Return the name of the object's exact type.
int	class_version () const
	Return the version of the class.
virtual void	print (std::ostream &=ExEnv::out0()) const
	Print the object.
Ref< DescribedClass >	ref ()
	Return this object wrapped up in a Ref smart pointer. More...
Public Member Functions inherited from sc::RefCount
size_t	identifier () const
	Return the unique identifier for this object that can be compared for different objects of different types. More...
int	lock_ptr () const
	Lock this object.
int	unlock_ptr () const
	Unlock this object.
void	use_locks (bool inVal)
	start and stop using locks on this object
refcount_t	nreference () const
	Return the reference count.
refcount_t	reference ()
	Increment the reference count and return the new count.
refcount_t	dereference ()
	Decrement the reference count and return the new count.
int	managed () const
void	unmanage ()
	Turn off the reference counting mechanism for this object. More...

Additional Inherited Members
Static Public Member Functions inherited from sc::MolecularGradient
static void	write_cartesian_gradient (const char *filename, const Ref< Molecule > &m, const RefSCVector &grad)
	Write the gradient in a simple text format.
static void	read_cartesian_gradient (const char *filename, const Ref< Molecule > &m, const RefSCVector &grad)
	Read the hessian from a simple text format.
Static Public Member Functions inherited from sc::SavableState
static void	save_state (SavableState *s, StateOut &)
static SavableState *	restore_state (StateIn &si)
	Restores objects saved with save_state. More...
static SavableState *	key_restore_state (StateIn &si, const char *keyword)
	Like restore_state, but keyword is used to override values while restoring.
static SavableState *	dir_restore_state (StateIn &si, const char *objectname, const char *keyword=0)
Protected Member Functions inherited from sc::SavableState
	SavableState (const SavableState &)
	SavableState (StateIn &)
	Each derived class StateIn CTOR handles the restore corresponding to calling save_object_state, save_vbase_state, and save_data_state listed above. More...
Protected Member Functions inherited from sc::RefCount
	RefCount (const RefCount &)
RefCount &	operator= (const RefCount &)
Protected Attributes inherited from sc::MolecularGradient
Ref< Molecule >	mol_
RefSCDimension	d3natom_
Ref< SCMatrixKit >	matrixkit_

Detailed Description

Computes the molecular gradient by finite differences of energies.

This will use the minimum number of displacements, each in the same point group as the reference geometry.

Constructor & Destructor Documentation

FinDispMolecularGradient()

sc::FinDispMolecularGradient::FinDispMolecularGradient

(

const Ref< KeyVal > &

)

The FinDispMolecularGradient KeyVal constructor is used to generate a FinDispMolecularGradient object from the input.

It reads the keywords below.

Keyword	Type	Default	Description
energy	MolecularEnergy	none	This gives an object which will be used to compute the energies needed to form the gradient. If this is not specified, the object using FinDispMolecularGradient will, in some cases, fill it in appropriately.
debug	boolean	false	If true, print out debugging information.
point_group	PointGroup	none	The point group to use for generating the displacements.
restart	boolean	true	If true, and a checkpoint file exists, restart from that file.
restart_file	string	basename.ckpt.grad	The name of the file where checkpoint information is written to or read from.
checkpoint	boolean	false	If true, checkpoint intermediate data.
eliminate_quadratic_terms	boolean	false	If true, then the terms quadratic in the displacement will be eliminated (i.e. the error in the gradient will be quartic in the displacement size). This requires that four displacements are done for each (totally symmetric) coordinate, rather than two. Setting this to true only makes sense for benchmark computations of high precision and should not be necessary in routine computations.
displacement	double	1.0e-2	The size of the displacement in Bohr.
energy_accuracy	double	accuracy * displacement	The accuracy to which the energies will be computed.

Member Function Documentation

cartesian_gradient()

RefSCVector sc::FinDispMolecularGradient::cartesian_gradient ( )

virtual

This returns the cartesian gradient.

If it has not yet been computed, it will be computed by finite displacements.

Implements sc::MolecularGradient.

energy()

MolecularEnergy* sc::FinDispMolecularGradient::energy ( ) const

virtual

This returns a MolecularEnergy object, if used by this specialization.

Otherwise null is returned.

Reimplemented from sc::MolecularGradient.

save_data_state()

void sc::FinDispMolecularGradient::save_data_state ( StateOut &  )

virtual

Save the base classes (with save_data_state) and the members in the same order that the StateIn CTOR initializes them.

This must be implemented by the derived class if the class has data.

Reimplemented from sc::MolecularGradient.

set_desired_accuracy()

void sc::FinDispMolecularGradient::set_desired_accuracy ( double  acc )

virtual

Sets the desired accuracy.

Parameters

acc	the desired accuracy

Reimplemented from sc::MolecularGradient.

set_energy()

void sc::FinDispMolecularGradient::set_energy ( const Ref< MolecularEnergy > &  energy )

virtual

Some MolecularGradient specializations require a molecular energy object.

The default implementations of this ignores the argument.

Reimplemented from sc::MolecularGradient.

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

• src/lib/chemistry/molecule/findisp.h