Iterator Class Reference

Base class for the iterator class hierarchy. More...

Inheritance diagram for Iterator:

List of all members.

Public Member Functions
	Iterator ()
	default constructor
	Iterator (Model &model)
	standard envelope constructor
	Iterator (const String &method_name, Model &model)
	alternate envelope constructor for instantiations by name
	Iterator (const Iterator &iterator)
	copy constructor
virtual	~Iterator ()
	destructor
Iterator	operator= (const Iterator &iterator)
	assignment operator
virtual void	initialize_run ()
	typically memory initialization; setting of instance pointers
virtual void	pre_run ()
	which can generate all Variables (parameter sets) a priori
virtual void	run ()
	and may include pre/post steps in lieu of separate pre/post
virtual void	post_run (std::ostream &s)
	perform final analysis phase in a standalone way
virtual void	finalize_run ()
	deallocation and resetting of instance pointers
virtual void	reset ()
	restore initial state for repeated sub-iterator executions
virtual const Variables &	variables_results () const
	return a single final iterator solution (variables)
virtual const Response &	response_results () const
	return a single final iterator solution (response)
virtual const VariablesArray &	variables_array_results ()
	only be used if returns_multiple_points() returns true.
virtual const ResponseArray &	response_array_results ()
	only be used if returns_multiple_points() returns true.
virtual bool	accepts_multiple_points () const
	return is false. Override to return true if appropriate.
virtual bool	returns_multiple_points () const
	return is false. Override to return true if appropriate.
virtual void	initial_points (const VariablesArray &pts)
	only be used if accepts_multiple_points() returns true.
virtual void	response_results_active_set (const ActiveSet &set)
	set the requested data for the final iterator response results
virtual void	initialize_graphics (bool graph_2d, bool tabular_data, const String &tabular_file)
	initialize the 2D graphics window and the tabular graphics data
virtual void	print_results (std::ostream &s)
	print the final iterator results
virtual int	num_samples () const
	get the current number of samples
virtual void	sampling_reset (int min_samples, bool all_data_flag, bool stats_flag)
	reset sampling iterator to use at least min_samples
virtual const String &	sampling_scheme () const
	return sampling name
virtual String	uses_method () const
	return name of any enabling iterator used by this iterator
virtual void	method_recourse ()
	perform a method switch, if possible, due to a detected conflict
virtual const VariablesArray &	all_variables ()
	return the complete set of evaluated variables
virtual const RealMatrix &	all_samples ()
	return the complete set of evaluated samples
virtual const ResponseArray &	all_responses () const
	return the complete set of computed responses
virtual bool	compact_mode () const
	returns Analyzer::compactMode
void	run_iterator (std::ostream &s)
	orchestrate initialize/pre/run/post/finalize phases
void	assign_rep (Iterator *iterator_rep, bool ref_count_incr=true)
	replaces existing letter with a new one
ProblemDescDB &	problem_description_db () const
	return the problem description database (probDescDB)
const String &	method_name () const
	return the method name
const String &	method_id () const
	return the method identifier (idMethod)
short	output_level () const
	return the method output level (outputLevel)
void	summary_output (bool summary_output_flag)
	Set summary output control; true enables evaluation/results summary.
int	maximum_concurrency () const
	return the maximum concurrency supported by the iterator
void	maximum_concurrency (int max_conc)
	set the maximum concurrency supported by the iterator
size_t	num_final_solutions () const
	return the number of solutions to retain in best variables/response arrays
void	num_final_solutions (size_t num_final)
	set the number of solutions to retain in best variables/response arrays
void	active_set (const ActiveSet &set)
	employ evaluate_parameter_sets())
const ActiveSet &	active_set () const
	employ evaluate_parameter_sets())
void	sub_iterator_flag (bool si_flag)
	set subIteratorFlag (and update summaryOutputFlag if needed)
void	active_variable_mappings (const SizetArray &c_index1, const SizetArray &di_index1, const SizetArray &dr_index1, const ShortArray &c_target2, const ShortArray &di_target2, const ShortArray &dr_target2)
	set primaryA{CV,DIV,DRV}MapIndices, secondaryA{CV,DIV,DRV}MapTargets
bool	is_null () const
	function to check iteratorRep (does this envelope contain a letter?)
Iterator *	iterator_rep () const
	that are not mapped to the top Iterator level
Protected Member Functions
	Iterator (BaseConstructor, Model &model)
	derived class constructors - Coplien, p. 139)
	Iterator (NoDBBaseConstructor, Model &model)
	alternate constructor for base iterator classes constructed on the fly
	Iterator (NoDBBaseConstructor)
	alternate constructor for base iterator classes constructed on the fly
virtual const VariablesArray &	initial_points () const
	be meaningful after a call to initial_points mutator.
Protected Attributes
Model	iteratedModel
	or a thin RecastModel wrapped around it
ProblemDescDB &	probDescDB
	class member reference to the problem description database
String	methodName
	name of the iterator (the user's method spec)
Real	convergenceTol
	iteration convergence tolerance
int	maxIterations
	maximum number of iterations for the iterator
int	maxFunctionEvals
	maximum number of fn evaluations for the iterator
int	maxConcurrency
	maximum coarse-grained concurrency
size_t	numFunctions
	number of response functions
size_t	numContinuousVars
	number of active continuous vars
size_t	numDiscreteIntVars
	number of active discrete integer vars
size_t	numDiscreteRealVars
	number of active discrete real vars
size_t	numFinalSolutions
	number of solutions to retain in best variables/response arrays
ActiveSet	activeSet
	tracks the response data requirements on each function evaluation
VariablesArray	bestVariablesArray
	collection of N best solution variables found during the study
ResponseArray	bestResponseArray
	collection of N best solution responses found during the study
bool	subIteratorFlag
	(NestedModel::subIterator or DataFitSurrModel::daceIterator)
SizetArray	primaryACVarMapIndices
	from higher level iteration
SizetArray	primaryADIVarMapIndices
	higher level iteration
SizetArray	primaryADRVarMapIndices
	higher level iteration
ShortArray	secondaryACVarMapTargets
	from higher level iteration
ShortArray	secondaryADIVarMapTargets
	from higher level iteration
ShortArray	secondaryADRVarMapTargets
	from higher level iteration
String	gradientType
	type of gradient data: analytic, numerical, mixed, or none
String	methodSource
	source of numerical gradient routine: dakota or vendor
String	intervalType
	type of numerical gradient interval: central or forward
String	hessianType
	type of Hessian data: analytic, numerical, quasi, mixed, or none
Real	fdGradStepSize
	relative finite difference step size for numerical gradients
Real	fdHessByGradStepSize
	using first-order differences of gradients
Real	fdHessByFnStepSize
	using second-order differences of function values
short	outputLevel
	output verbosity level: {SILENT,QUIET,NORMAL,VERBOSE,DEBUG}_OUTPUT
bool	summaryOutputFlag
	sub-iterator use cases
bool	asynchFlag
	copy of the model's asynchronous evaluation flag
int	writePrecision
	write precision as specified by the user
Private Member Functions
Iterator *	get_iterator (Model &model)
	Used by the envelope to instantiate the correct letter class.
Iterator *	get_iterator (const String &method_name, Model &model)
	Used by the envelope to instantiate the correct letter class.
virtual void	pre_output ()
	convenience function to write variables to file, following pre-run
virtual void	post_input ()
	read tabular data for post-run mode
Private Attributes
String	idMethod
	method identifier string from the input file
Iterator *	iteratorRep
	pointer to the letter (initialized only for the envelope)
int	referenceCount
	number of objects sharing iteratorRep

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Detailed Description

Base class for the iterator class hierarchy.

The Iterator class is the base class for one of the primary class hierarchies in DAKOTA. The iterator hierarchy contains all of the iterative algorithms which use repeated execution of simulations as function evaluations. For memory efficiency and enhanced polymorphism, the iterator hierarchy employs the "letter/envelope idiom" (see Coplien "Advanced C++", p. 133), for which the base class (Iterator) serves as the envelope and one of the derived classes (selected in Iterator::get_iterator()) serves as the letter.

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Constructor & Destructor Documentation

Iterator

(

)

default constructor

The default constructor is used in Vector<Iterator> instantiations and for initialization of Iterator objects contained in Strategy derived classes (see derived class header files). iteratorRep is NULL in this case (a populated problem_db is needed to build a meaningful Iterator object). This makes it necessary to check for NULL pointers in the copy constructor, assignment operator, and destructor.

Iterator

(

Model &

model

)

standard envelope constructor

Used in iterator instantiations within strategy constructors. Envelope constructor only needs to extract enough data to properly execute get_iterator(), since letter holds the actual base class data.

Iterator	(	const String &	method_name,
		Model &	model
	)

alternate envelope constructor for instantiations by name

Used in sub-iterator instantiations within iterator constructors. Envelope constructor only needs to extract enough data to properly execute get_iterator(), since letter holds the actual base class data.

Iterator

(

const Iterator &

iterator

)

copy constructor

Copy constructor manages sharing of iteratorRep and incrementing of referenceCount.

~Iterator

(

)

[virtual]

destructor

Destructor decrements referenceCount and only deletes iteratorRep when referenceCount reaches zero.

Iterator	(	BaseConstructor	,
		Model &	model
	)			[protected]

derived class constructors - Coplien, p. 139)

This constructor builds the base class data for all inherited iterators. get_iterator() instantiates a derived class and the derived class selects this base class constructor in its initialization list (to avoid the recursion of the base class constructor calling get_iterator() again). Since the letter IS the representation, its representation pointer is set to NULL (an uninitialized pointer causes problems in ~Iterator).

Iterator	(	NoDBBaseConstructor	,
		Model &	model
	)			[protected]

alternate constructor for base iterator classes constructed on the fly

This alternate constructor builds base class data for inherited iterators. It is used for on-the-fly instantiations for which DB queries cannot be used. Therefore it only sets attributes taken from the incoming model. Since there are no iterator-specific redefinitions of maxIterations or numFinalSolutions in NoDBBaseConstructor mode, go ahead and assign default value for all iterators.

Iterator

(

NoDBBaseConstructor

)

[protected]

alternate constructor for base iterator classes constructed on the fly

This alternate constructor builds base class data for inherited iterators. It is used for on-the-fly instantiations for which DB queries cannot be used. It has no incoming model, so only sets up a minimal set of defaults. However, its use is preferable to the default constructor, which should remain as minimal as possible. Since there are no iterator-specific redefinitions of maxIterations or numFinalSolutions in NoDBBaseConstructor mode, go ahead and assign default value for all iterators.

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Member Function Documentation

Iterator operator=

(

const Iterator &

iterator

)

assignment operator

Assignment operator decrements referenceCount for old iteratorRep, assigns new iteratorRep, and increments referenceCount for new iteratorRep.

void initialize_run

(

)

[virtual]

typically memory initialization; setting of instance pointers

Perform initialization phases of run sequence, like allocating memory and setting instance pointers. Commonly used in sub-iterator executions. This is a virtual function; when re-implementing, a derived class must call its nearest parent's initialize_run(), typically _before_ performing its own implementation steps.

Reimplemented in CONMINOptimizer, LeastSq, Minimizer, NonD, Optimizer, DOTOptimizer, NLPQLPOptimizer, SNLLLeastSq, and SNLLOptimizer.

void pre_run

(

)

[virtual]

which can generate all Variables (parameter sets) a priori

pre-run phase, which a derived iterator may optionally reimplement; when not present, pre-run is likely integrated into the derived run function. This is a virtual function; when re-implementing, a derived class must call its nearest parent's pre_run(), if implemented, typically _before_ performing its own implementation steps.

Reimplemented in DDACEDesignCompExp, FSUDesignCompExp, NonDLHSSampling, ParamStudy, and PSUADEDesignCompExp.

void run

(

)

[virtual]

and may include pre/post steps in lieu of separate pre/post

Virtual run function for the iterator class hierarchy. All derived classes need to redefine it.

Reimplemented in LeastSq, NonD, Optimizer, PStudyDACE, Verification, and SurrBasedMinimizer.

void post_run

(

std::ostream &

s

)

[virtual]

perform final analysis phase in a standalone way

Post-run phase, which a derived iterator may optionally reimplement; when not present, post-run is likely integrated into run. This is a virtual function; when re-implementing, a derived class must call its nearest parent's post_run(), typically _after_ performing its own implementation steps.

Reimplemented in COLINOptimizer, LeastSq, Optimizer, DDACEDesignCompExp, FSUDesignCompExp, NonDLHSSampling, ParamStudy, PSUADEDesignCompExp, SNLLLeastSq, and SNLLOptimizer.

void finalize_run

(

)

[virtual]

deallocation and resetting of instance pointers

Optional: perform finalization phases of run sequence, like deallocating memory and resetting instance pointers. Commonly used in sub-iterator executions. This is a virtual function; when re-implementing, a derived class must call its nearest parent's finalize_run(), typically _after_ performing its own implementation steps.

Reimplemented in LeastSq, Minimizer, NonD, Optimizer, SNLLLeastSq, and SNLLOptimizer.

void initialize_graphics	(	bool	graph_2d,
		bool	tabular_data,
		const String &	tabular_file
	)			[virtual]

initialize the 2D graphics window and the tabular graphics data

This is a convenience function for encapsulating graphics initialization operations. It does not require a strategyRep forward since it is only used by letter objects.

Reimplemented in NonDReliability, and SurrBasedMinimizer.

void print_results

(

std::ostream &

s

)

[virtual]

print the final iterator results

This virtual function provides additional iterator-specific final results outputs beyond the function evaluation summary printed in finalize_run().

Reimplemented in Analyzer, LeastSq, Optimizer, PStudyDACE, Verification, NonDExpansion, NonDGlobalReliability, NonDGPMSABayesCalibration, NonDIncremLHSSampling, NonDInterval, NonDLHSSampling, NonDLocalReliability, RichExtrapVerification, and SurrBasedMinimizer.

int num_samples

(

)

const [virtual]

get the current number of samples

Return current number of evaluation points. Since the calculation of samples, collocation points, etc. might be costly, provide a default implementation here that backs out from the maxConcurrency. May be (is) overridden by derived classes.

Reimplemented in DDACEDesignCompExp, FSUDesignCompExp, NonDSampling, and PSUADEDesignCompExp.

void run_iterator

(

std::ostream &

s

)

orchestrate initialize/pre/run/post/finalize phases

Iterator supports a construct/initialize-run/pre-run/run/post-run/finalize-run/destruct progression. This member (non-virtual) function sequences these run phases; it accepts an ostream, but controls verbosity with outputLevel

void assign_rep	(	Iterator *	iterator_rep,
		bool	ref_count_incr = true
	)

replaces existing letter with a new one

Similar to the assignment operator, the assign_rep() function decrements referenceCount for the old iteratorRep and assigns the new iteratorRep. It is different in that it is used for publishing derived class letters to existing envelopes, as opposed to sharing representations among multiple envelopes (in particular, assign_rep is passed a letter object and operator= is passed an envelope object). Letter assignment supports two models as governed by ref_count_incr:

• ref_count_incr = true (default): the incoming letter belongs to another envelope. In this case, increment the reference count in the normal manner so that deallocation of the letter is handled properly.

• ref_count_incr = false: the incoming letter is instantiated on the fly and has no envelope. This case is modeled after get_iterator(): a letter is dynamically allocated using new and passed into assign_rep, the letter's reference count is not incremented, and the letter is not remotely deleted (its memory management is passed over to the envelope).

Iterator * get_iterator

(

Model &

model

)

[private]

Used by the envelope to instantiate the correct letter class.

Used only by the envelope constructor to initialize iteratorRep to the appropriate derived type, as given by the methodName attribute.

Iterator * get_iterator	(	const String &	method_name,
		Model &	model
	)			[private]

Used by the envelope to instantiate the correct letter class.

Used only by the envelope constructor to initialize iteratorRep to the appropriate derived type, as given by the passed method_name.

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Member Data Documentation

Real fdGradStepSize [protected]

relative finite difference step size for numerical gradients

A scalar value (instead of the vector fd_gradient_step_size spec) is used within the iterator hierarchy since this attribute is only used to publish a step size to vendor numerical gradient algorithms.

Real fdHessByGradStepSize [protected]

using first-order differences of gradients

A scalar value (instead of the vector fd_hessian_step_size spec) is used within the iterator hierarchy since this attribute is only used to publish a step size to vendor numerical Hessian algorithms.

Real fdHessByFnStepSize [protected]

using second-order differences of function values

A scalar value (instead of the vector fd_hessian_step_size spec) is used within the iterator hierarchy since this attribute is only used to publish a step size to vendor numerical Hessian algorithms.

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

• DakotaIterator.H
• DakotaIterator.C

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