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 constructor for envelope
	Iterator (const Iterator &iterator)
	copy constructor
virtual	~Iterator ()
	destructor
Iterator	operator= (const Iterator &iterator)
	assignment operator
virtual void	run_iterator ()
	run the iterator
virtual const Variables &	iterator_variable_results () const
	return the final iterator solution (variables)
virtual const Response &	iterator_response_results () const
	return the final iterator solution (response)
virtual void	print_iterator_results (ostream &s) const
	print the final iterator results
virtual void	multi_objective_weights (const RealVector &multi_obj_wts)
	set the relative weightings for multiple objective functions. Used by ConcurrentStrategy for Pareto set optimization.
virtual void	sampling_reset (int min_samples, bool all_data_flag, bool stats_flag)
	reset sampling iterator
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 () const
	return the complete set of evaluated variables
virtual const RealVectorArray &	all_c_variables () const
	return the complete set of evaluated continuous variables
virtual const ResponseArray &	all_responses () const
	return the complete set of computed responses
virtual const RealVectorArray &	all_fn_responses () const
	return the complete set of computed function responses
void	assign_rep (Iterator *iterator_rep)
	replaces existing letter with a new one
void	user_defined_model (const Model &the_model)
	set the model
Model	user_defined_model () const
	return the model
const String &	method_name () const
	return the method name
const int &	maximum_concurrency () const
	return the maximum concurrency supported by the iterator
void	active_set_vector (const IntArray &asv)
	set the default active set vector (for use with iterators that employ evaluate_parameter_sets())
void	iterator_response_results_asv (const IntArray &asv)
	set the requested data for the final iterator response results
void	sub_iterator_flag (bool si_flag)
	set subIteratorFlag
bool	is_null () const
	function to check iteratorRep (does this envelope contain a letter?)
Protected Member Functions
	Iterator (BaseConstructor, Model &model)
	constructor initializes the base class part of letter classes (BaseConstructor overloading avoids infinite recursion in the derived class constructors - Coplien, p. 139)
	Iterator (NoDBBaseConstructor, Model &model)
	base class for iterator classes constructed on the fly (no DB queries)
Protected Attributes
Model	userDefinedModel
	shallow copy (shared rep) of the model passed into the constructor. A class member reference is not needed in this case due to the presence of representation sharing in Models.
const ProblemDescDB &	probDescDB
	class member reference to the problem description database
String	methodName
	name of the iterator (the user's method spec)
int	maxIterations
	maximum number of iterations for the iterator
int	maxFunctionEvals
	maximum number of fn evaluations for the iterator
int	numFunctions
	number of response functions
int	maxConcurrency
	maximum coarse-grained concurrency
int	numContinuousVars
	number of active continuous vars.
int	numDiscreteVars
	number of active discrete vars.
int	numVars
	total number of vars. (active and inactive)
IntArray	activeSetVector
	this vector tracks the data requirements for the response functions. It uses a 0 value for inactive functions and, for active functions, sums 1 for value, 2 for gradient, and 4 for Hessian.
IntArray	finalResultsASV
	this active set vector specifies the required final results to be returned by iterator_response_results()
bool	subIteratorFlag
	flag indicating if this Iterator is a sub-iterator (NestedModel::subIterator) or SurrLayeredModel::daceIterator).
String	gradientType
	type of gradient data: analytic, numerical, mixed, or none
String	intervalType
	type of numerical gradient interval: central or forward
String	methodSource
	source of numerical gradient routine: dakota or vendor
String	hessianType
	type of Hessian data: analytic, numerical, quasi, mixed, or none
Real	fdGradStepSize
	relative finite difference step size for numerical gradients
Real	fdHessByGradStepSize
	relative finite difference step size for numerical Hessians estimated using first-order differences of gradients
Real	fdHessByFnStepSize
	relative finite difference step size for numerical Hessians estimated using second-order differences of function values
bool	silentOutput
	flag for really quiet (silent) algorithm output
bool	quietOutput
	flag for quiet algorithm output
bool	verboseOutput
	flag for verbose algorithm output
bool	debugOutput
	flag for really verbose (debug) algorithm output
bool	asynchFlag
	copy of the model's asynchronous evaluation flag
Private Member Functions
Iterator *	get_iterator (Model &model)
	Used by the envelope to instantiate the correct letter class.
Private Attributes
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 constructor for envelope Used in iterator instantiations within strategy constructors. Envelope constructor only needs to extract enough data to properly execute get_iterator, since Iterator(BaseConstructor, model) builds the actual base class data inherited by the derived iterators.

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]

constructor initializes the base class part of letter classes (BaseConstructor overloading avoids infinite recursion in the 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]

base class for iterator classes constructed on the fly (no DB queries) This constructor also builds base class data for inherited iterators. However, it is used for on-the-fly instantiations for which DB queries cannot be used (e.g., ApproximationInterface instantiation of DDACEDesignCompExp or NonDSampling, NonDReliability usage of optimizers, etc.). Therefore it only sets attributes taken from the incoming model.

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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 run_iterator (   )  [virtual]

run the iterator This function is the primary run function for the iterator class hierarchy. All derived classes need to redefine it. Reimplemented in LeastSq, NonD, Optimizer, and PStudyDACE.

void assign_rep (  Iterator *  iterator_rep  )

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 is modeled after get_iterator() in that it does not increment the referenceCount for the new iteratorRep.

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.

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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]

relative finite difference step size for numerical Hessians estimated 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]

relative finite difference step size for numerical Hessians estimated 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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