Epetra_MapColoring: A class for coloring Epetra_Map and Epetra_BlockMap objects. More...

#include <Epetra_MapColoring.h>

Inheritance diagram for Epetra_MapColoring:

Collaboration diagram for Epetra_MapColoring:

Public Member Functions
Constructors/destructors
	Epetra_MapColoring (const Epetra_BlockMap &Map, const int DefaultColor=0)
	Epetra_MapColoring basic constructor. More...

	Epetra_MapColoring (const Epetra_BlockMap &Map, int *ElementColors, const int DefaultColor=0)
	Epetra_MapColoring constructor. More...

	Epetra_MapColoring (const Epetra_MapColoring &Source)
	Epetra_MapColoring copy constructor.

virtual	~Epetra_MapColoring ()
	Epetra_MapColoring destructor.

Set Color methods
int &	operator[] (int LID)
	LID element color assignment method. More...

int &	operator() (long long GID)
	GID element color assignment method, Note: Valid only for GIDs owned by calling processor. More...

Local/Global color accessor methods
const int &	operator[] (int LID) const
	LID element color access method. More...

const int &	operator() (long long GID) const
	GID element color assignment method, Note: Valid only for GIDs owned by calling processor. More...

Color Information Access Methods
int	NumColors () const
	Returns number of colors on the calling processor.

int	MaxNumColors () const
	Returns maximum over all processors of the number of colors.

int *	ListOfColors () const
	Array of length NumColors() containing List of color values used in this coloring. More...

int	DefaultColor () const
	Returns default color.

int	NumElementsWithColor (int Color) const
	Returns number of map elements on calling processor having specified Color.

int *	ColorLIDList (int Color) const
	Returns pointer to array of Map LIDs associated with the specified color. More...

int *	ElementColors () const
	Returns pointer to array of the colors associated with the LIDs on the calling processor. More...

Epetra_Map and Epetra_BlockMap generators
Epetra_Map *	GenerateMap (int Color) const
	Generates an Epetra_Map of the GIDs associated with the specified color. More...

Epetra_BlockMap *	GenerateBlockMap (int Color) const
	Generates an Epetra_BlockMap of the GIDs associated with the specified color. More...

I/O methods
virtual void	Print (std::ostream &os) const
	Print method.

Public Member Functions inherited from Epetra_DistObject
	Epetra_DistObject (const Epetra_BlockMap &Map)
	Basic Epetra_DistObject constuctor. More...

	Epetra_DistObject (const Epetra_BlockMap &Map, const char *const Label)

	Epetra_DistObject (const Epetra_DistObject &Source)
	Epetra_DistObject copy constructor.

virtual	~Epetra_DistObject ()
	Epetra_DistObject destructor.

int	Import (const Epetra_SrcDistObject &A, const Epetra_Import &Importer, Epetra_CombineMode CombineMode, const Epetra_OffsetIndex *Indexor=0)
	Imports an Epetra_DistObject using the Epetra_Import object. More...

int	Import (const Epetra_SrcDistObject &A, const Epetra_Export &Exporter, Epetra_CombineMode CombineMode, const Epetra_OffsetIndex *Indexor=0)
	Imports an Epetra_DistObject using the Epetra_Export object. More...

int	Export (const Epetra_SrcDistObject &A, const Epetra_Import &Importer, Epetra_CombineMode CombineMode, const Epetra_OffsetIndex *Indexor=0)
	Exports an Epetra_DistObject using the Epetra_Import object. More...

int	Export (const Epetra_SrcDistObject &A, const Epetra_Export &Exporter, Epetra_CombineMode CombineMode, const Epetra_OffsetIndex *Indexor=0)
	Exports an Epetra_DistObject using the Epetra_Export object. More...

const Epetra_BlockMap &	Map () const
	Returns the address of the Epetra_BlockMap for this multi-vector.

const Epetra_Comm &	Comm () const
	Returns the address of the Epetra_Comm for this multi-vector.

bool	DistributedGlobal () const
	Returns true if this multi-vector is distributed global, i.e., not local replicated.

Public Member Functions inherited from Epetra_Object
	Epetra_Object (int TracebackModeIn=-1, bool set_label=true)
	Epetra_Object Constructor. More...

	Epetra_Object (const char *const Label, int TracebackModeIn=-1)
	Epetra_Object Constructor. More...

	Epetra_Object (const Epetra_Object &Object)
	Epetra_Object Copy Constructor. More...

virtual	~Epetra_Object ()
	Epetra_Object Destructor. More...

virtual int	ReportError (const std::string Message, int ErrorCode) const
	Error reporting method.

virtual void	SetLabel (const char *const Label)
	Epetra_Object Label definition using char *. More...

virtual const char *	Label () const
	Epetra_Object Label access funtion. More...

Public Member Functions inherited from Epetra_SrcDistObject
virtual	~Epetra_SrcDistObject ()
	Epetra_SrcDistObject destructor.

Additional Inherited Members
Static Public Member Functions inherited from Epetra_Object
static void	SetTracebackMode (int TracebackModeValue)
	Set the value of the Epetra_Object error traceback report mode. More...

static int	GetTracebackMode ()
	Get the value of the Epetra_Object error report mode.

static std::ostream &	GetTracebackStream ()
	Get the output stream for error reporting.

Static Public Attributes inherited from Epetra_Object
static int	TracebackMode

Protected Member Functions inherited from Epetra_DistObject
virtual int	DoTransfer (const Epetra_SrcDistObject &A, Epetra_CombineMode CombineMode, int NumSameIDs, int NumPermuteIDs, int NumRemoteIDs, int NumExportIDs, int PermuteToLIDs, int PermuteFromLIDs, int RemoteLIDs, int ExportLIDs, int &LenExports, char &Exports, int &LenImports, char &Imports, Epetra_Distributor &Distor, bool DoReverse, const Epetra_OffsetIndex *Indexor)
	Perform actual transfer (redistribution) of data across memory images, using Epetra_Distributor object.

Protected Member Functions inherited from Epetra_Object
std::string	toString (const int &x) const

std::string	toString (const long long &x) const

std::string	toString (const double &x) const

Protected Attributes inherited from Epetra_DistObject
Epetra_BlockMap	Map_

const Epetra_Comm *	Comm_

char *	Exports_

char *	Imports_

int	LenExports_

int	LenImports_

int *	Sizes_

Detailed Description

Epetra_MapColoring: A class for coloring Epetra_Map and Epetra_BlockMap objects.

This class allows the user to associate an integer value, i.e., a color, to each element of
an existing Epetra_Map or Epetra_BlockMap object.  Colors may be assigned at construction, or
via set methods.  Any elements that are not explicitly assigned a color are assigned the color
0 (integer zero).

This class has the following features:

A color (arbitrary integer label) can be associated locally with each element of a map. Color assignment can be done
1. all-at-once via the constructor, or
2. via operator[] (using LIDs) one-at-a-time
3. operator() (using GIDs) one-at-a-time
4. or some combination of the above.
Any element that is not explicitly colored takes on the default color. The default color is implicitly zero, unless specified differently at the time of construction.
Color information may be accessed in the following ways:
1. By local element ID (LID) - Returns the color of a specified LID, where the LID is associated with the Epetra_Map or BlockMap that was passed in to the Epetra_MapColoring constructor.
2. By global element ID (GID) - Returns the color of the specified GID. There two methods for accessing GIDs, one assumes the request is for GIDs owned by the calling processor, the second allows arbitrary requested for GIDs, as long as the GID is defined on some processor for the Epetra_Map or Epetra_BlockMap.
3. By color groups - Elements are grouped by color so that all elements of a given color can be accessed.
4. Epetra_Map/Epetra_BlockMap pointers for a specified color - This facilitates use of coloring with Epetra distributed objects that are distributed via the map that was colored. For example, if users want to work with all rows of a matrix that have a certain color, they can create a map for that color and use it to access only those rows.
The Epetra_MapColoring class implements the Epetra_DistObject interface. Therefore, a map coloring can be computed for a map with a given distribution and then redistributed across the parallel machine. For example, it would be possible to compute a map coloring on a single processor (perhaps because the algorithm for computing the color assignment is too difficult to implement in parallel or because it is cheap to run and not worth parallelizing), and then re-distribute the coloring using an Epetra_Export or Epetra_Import object.

Constructor & Destructor Documentation

Epetra_MapColoring::Epetra_MapColoring	(	const Epetra_BlockMap &	Map,
		const int	DefaultColor = `0`
	)

Epetra_MapColoring basic constructor.

Parameters

In	Map - An Epetra_Map or Epetra_BlockMap (Note: Epetra_BlockMap is a base class of Epetra_Map, so either can be passed in to this constructor.
In	DefaultColor - The integer value to use as the default color for this map. This constructor will initially define the color of all map elements to the default color.

Returns: Pointer to a Epetra_MapColoring object.

Epetra_MapColoring::Epetra_MapColoring	(	const Epetra_BlockMap &	Map,
		int *	ElementColors,
		const int	DefaultColor = `0`
	)

Epetra_MapColoring constructor.

Parameters

In	Map - An Epetra_Map or Epetra_BlockMap (Note: Epetra_BlockMap is a base class of Epetra_Map, so either can be passed in to this constructor.
In	ElementColors - Array of dimension Map.NumMyElements() containing the list of colors that should be assigned the map elements on this processor. If this argument is set to 0 (zero), all elements will initially be assigned color 0 (zero). Element colors can be modified by using methods described below.
In	DefaultColor - The color that will be assigned by default when no other value is specified. This value has no meaning for this constructor, but is used by certain methods now and in the future.

Returns: Pointer to a Epetra_MapColoring object.

Member Function Documentation

int* Epetra_MapColoring::ColorLIDList ( int Color ) const

Returns pointer to array of Map LIDs associated with the specified color.

Returns a pointer to a list of Map LIDs associated with the specified color. This is a purely local list with no information about other processors. If there are no LIDs associated with the specified color, the pointer is set to zero.

int* Epetra_MapColoring::ElementColors ( ) const

inline

Returns pointer to array of the colors associated with the LIDs on the calling processor.

Returns a pointer to the list of colors associated with the elements on this processor such that ElementColor[LID] is the color assigned to that LID.

Epetra_BlockMap* Epetra_MapColoring::GenerateBlockMap ( int Color ) const

Generates an Epetra_BlockMap of the GIDs associated with the specified color.

This method will create an Epetra_BlockMap such that on each processor the GIDs associated with the specified color will be part of the map on that processor. Note that this method will generate an Epetra_BlockMap such that each element as the same element size as the corresponding element of map associated with the map coloring. Once the map is generated, the user is responsible for deleting it.

Epetra_Map* Epetra_MapColoring::GenerateMap ( int Color ) const

Generates an Epetra_Map of the GIDs associated with the specified color.

This method will create an Epetra_Map such that on each processor the GIDs associated with the specified color will be part of the map on that processor. Note that this method always generates an Epetra_Map, not an Epetra_BlockMap, even if the map associated with this map coloring is a block map. Once the map is generated, the user is responsible for deleting it.

int* Epetra_MapColoring::ListOfColors ( ) const

inline

Array of length NumColors() containing List of color values used in this coloring.

Color values can be arbitrary integer values. As a result, a user of a previously constructed MapColoring object may need to know exactly which color values are present. This array contains that information as a sorted list of integer values.

int& Epetra_MapColoring::operator() ( long long GID )

inline

GID element color assignment method, Note: Valid only for GIDs owned by calling processor.

Allows color assignment of specified GID only if the GID is owned by map on the calling processor. If you are unsure about the ownership of a GID, check by using the MyGID() method. MyGID(GID) returns true if the GID is owned by the calling processor.

Returns: MapColor(GID).

References Epetra_BlockMap::LID(), and Epetra_DistObject::Map().

const int& Epetra_MapColoring::operator() ( long long GID ) const

inline

GID element color assignment method, Note: Valid only for GIDs owned by calling processor.

Allows color assignment of specified GID only if the GID is owned by map on the calling processor. If you are unsure about the ownership, check by using the MyGID() method on the map object.

Returns: MapColor(GID).

References Epetra_BlockMap::LID(), and Epetra_DistObject::Map().

int& Epetra_MapColoring::operator[] ( int LID )

inline

LID element color assignment method.

Allows color assignment of ith LID: colormap[i] = color

Returns: MapColor(LID).

const int& Epetra_MapColoring::operator[] ( int LID ) const

inline

LID element color access method.

Returns color of ith LID: colormap[i] = color

Returns: MapColor[LID].

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

Epetra_MapColoring.h

Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation