operations_research::TrivialSolutionGenerator Class Reference

The consistency level is maintained up to kFreeAndUncovered. More...

Detailed Description

The consistency level is maintained up to kFreeAndUncovered.

An obvious idea is to take all the S_j's (or equivalently to set all the x_j's to 1). It's very silly but fast, and we can improve on it later using local search.

Definition at line 245 of file set_cover_heuristics.h.

#include <set_cover_heuristics.h>

Inheritance diagram for operations_research::TrivialSolutionGenerator:

Public Member Functions
	TrivialSolutionGenerator (SetCoverInvariant *inv)
	TrivialSolutionGenerator (SetCoverInvariant *inv, absl::string_view name)
bool	NextSolution (absl::Span< const SubsetIndex > focus) final
	TrivialSolutionGenerator.
bool	NextSolution () final
	Virtual methods that must be implemented by derived classes.
bool	NextSolution (const SubsetBoolVector &in_focus) final
	Same as above, but with a vector of Booleans as focus.
Public Member Functions inherited from operations_research::SubsetListBasedSolutionGenerator
	SubsetListBasedSolutionGenerator (SetCoverInvariant *inv, SetCoverInvariant::ConsistencyLevel consistency_level, absl::string_view class_name, absl::string_view name)
Public Member Functions inherited from operations_research::SetCoverSolutionGenerator
	SetCoverSolutionGenerator (SetCoverInvariant *inv, SetCoverInvariant::ConsistencyLevel consistency_level, absl::string_view class_name, absl::string_view name)
virtual	~SetCoverSolutionGenerator ()=default
void	SetName (const absl::string_view name)
SetCoverInvariant *	inv () const
virtual SetCoverSolutionGenerator &	ResetLimits ()
	Resets the limits to their default values.
SetCoverSolutionGenerator &	SetMaxIterations (int64_t max_iterations)
	Sets the maximum number of iterations.
int64_t	max_iterations () const
	Returns the maximum number of iterations.
SetCoverSolutionGenerator &	SetTimeLimitInSeconds (double seconds)
	Sets the time limit in seconds.
absl::Duration	run_time () const
double	run_time_in_seconds () const
	Returns the total elapsed runtime in seconds.
double	run_time_in_microseconds () const
	Returns the total elapsed runtime in microseconds.
std::string	name () const
	Returns the name of the heuristic.
std::string	class_name () const
	Returns the name of the class.
Cost	cost () const
	Returns the current cost of the solution in the invariant.
bool	CheckInvariantConsistency () const

Additional Inherited Members
Protected Member Functions inherited from operations_research::SetCoverSolutionGenerator
SetCoverModel *	model () const
	Accessors.
BaseInt	num_subsets () const
double	time_limit_in_seconds () const
	The time limit in seconds.
Protected Attributes inherited from operations_research::SetCoverSolutionGenerator
absl::Duration	run_time_
	run_time_ is an abstract duration for the time spent in NextSolution().
SetCoverInvariant::ConsistencyLevel	consistency_level_
	The consistency needed by the solution generator.

Constructor & Destructor Documentation

TrivialSolutionGenerator() [1/2]

operations_research::TrivialSolutionGenerator::TrivialSolutionGenerator ( SetCoverInvariant * inv )

inlineexplicit

Definition at line 247 of file set_cover_heuristics.h.

TrivialSolutionGenerator() [2/2]

operations_research::TrivialSolutionGenerator::TrivialSolutionGenerator ( SetCoverInvariant * inv, absl::string_view name )

inline

Definition at line 250 of file set_cover_heuristics.h.

Member Function Documentation

NextSolution() [1/3]

bool operations_research::SubsetListBasedSolutionGenerator::NextSolution ( )

inlinefinalvirtual

Virtual methods that must be implemented by derived classes.

Computes the next full solution taking into account all the subsets.

Reimplemented from operations_research::SubsetListBasedSolutionGenerator.

Definition at line 181 of file set_cover_heuristics.h.

NextSolution() [2/3]

bool operations_research::TrivialSolutionGenerator::NextSolution ( absl::Span< const SubsetIndex > focus )

finalvirtual

TrivialSolutionGenerator.

Reimplemented from operations_research::SubsetListBasedSolutionGenerator.

Definition at line 51 of file set_cover_heuristics.cc.

NextSolution() [3/3]

bool operations_research::SubsetListBasedSolutionGenerator::NextSolution ( const SubsetBoolVector & in_focus )

inlinefinalvirtual

Same as above, but with a vector of Booleans as focus.

Reimplemented from operations_research::SubsetListBasedSolutionGenerator.

Definition at line 183 of file set_cover_heuristics.h.

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

• ortools/set_cover/set_cover_heuristics.h
• ortools/set_cover/set_cover_heuristics.cc