PyTrilinos.Epetra.Map Class Reference

Inheritance diagram for PyTrilinos.Epetra.Map:

Collaboration diagram for PyTrilinos.Epetra.Map:

List of all members.

Public Member Functions
def	__init__
Public Attributes
	this

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Detailed Description

Epetra_Map: A class for partitioning vectors and matrices.

It is often the case that multiple matrix and vector objects have an
identical distribution of elements on a parallel machine. The
Epetra_Map class keep information that describes this distribution for
matrices and vectors.

Epetra_Map allows the storage and retrieval of the following
information. Depending on the constructor that is used, some of the
information is defined by the user and some is determined by the
constructor. Once a Epetra_Map is constructed any of the following
attributes can be obtained by calling a query function that has the
name as the attribute, e.g. to get the value of NumGlobalElements, you
can call a function NumGlobalElements(). For attributes that are
lists, the query functions return the list values in a user allocated
array.

NumGlobalElements - The total number of elements across all
processors. If this parameter and NumMyElements are both passed into
the constructor, one of the three cases will apply: If
NumGlobalElements = NumMyElements (and not equal to zero) the map is
defined to be a local replicated map. In this case, objects
constructed using this map will be identically replicated across all
processors in the communicator.

If NumGlobalElements = -1 and NumMyElements is passed in then
NumGlobalElements will be computed as the sum of NumMyElements across
all processors.

If neither of the above is true, NumGlobalElements will be checked
against the sum of NumMyElements across all processors. An error is
issued if the comparison is not equal.

NumMyElements - The number of elements owned by the calling processor.

MyGlobalElements - A list of length NumMyElements that contains the
global element IDs of the elements owned by the calling processor.

IndexBase - The base integer value for indexed array references.
Typically this is 0 for C/C++ and 1 for Fortran, but it can be set to
any integer value.

Comm - The Epetra_Comm communicator. This communicator can in turn be
queried for processor rank and size information.

In addition to the information above that is passed in to or created
by the Epetra_Map constructor, the following attributes are computed
and available via query to the user using the same scheme as above,
e.g., use NumGlobalPoints() to get the value of NumGlobalPoints.

NumGlobalPoints - The total number of points across all processors.

NumMyPoints - The number of points on the calling processor.

MinAllGID - The minimum global index value across all processors.

MaxAllGID - The maximum global index value across all processors.

MinMyGID - The minimum global index value on the calling processor.

MaxMyGID - The maximum global index value on the calling processor.

MinLID - The minimum local index value on the calling processor.

MaxLID - The maximum local index value on the calling processor.

The following functions allow boolean tests for certain properties.

LinearMap() - Returns true if the elements are distributed linear
across processors, i.e., processor 0 gets the first n/p elements,
processor 1 gets the next n/p elements, etc. where n is the number of
elements and p is the number of processors.

DistributedGlobal() - Returns true if the element space of the map
spans more than one processor. This will be true in most cases, but
will be false in serial cases and for objects that are created via the
derived Epetra_LocalMap class.

WARNING:  An Epetra_Comm object is required for all Epetra_Map
constructors.

In the current implementation, Epetra_BlockMap is the base class for
Epetra_Map.

C++ includes: Epetra_Map.h 

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Constructor & Destructor Documentation

def PyTrilinos.Epetra.Map.__init__	(		self,
			args
	)

__init__(self, int numGlobalElements, int indexBase, Comm comm) -> Map

Map constructor with implicit number of elements per processor.
Arguments are:

     numGlobalElements  - Total number of elements over all processors.
                  Specify -1 to have the constructor compute
                  the number of global elements
     indexBase          - The base integer value for indexed array
                  references.  Typically this is 0 for C/C++ and 1
                  for Fortran, but it can be set to any integer
                  value.
     comm               - The Epetra.Comm communicator. This communicator
                  can in turn be queried for processor rank and
                  size information.
__init__(Epetra_Map self, long long NumGlobalElements, int IndexBase, Comm Comm) -> Map

__init__(self, int numGlobalElements, int numMyElements, int indexBase,
     Comm comm) -> Map

Map constructor with specified number of elements per processor.
Arguments are:

     numGlobalElements  - Total number of elements over all processors.
                  Specify -1 to have the constructor compute
                  the number of global elements
     numMyElements      - Number of local elements on this processor.
     indexBase          - The base integer value for indexed array
                  references.  Typically this is 0 for C/C++ and 1
                  for Fortran, but it can be set to any integer
                  value.
     comm               - The Epetra.Comm communicator. This communicator
                  can in turn be queried for processor rank and
                  size information.
__init__(Epetra_Map self, long long NumGlobalElements, int NumMyElements, int IndexBase, Comm Comm) -> Map

__init__(self, int numGlobalElements, PySequence myGlobalElements,
     int indexBase, Comm comm) -> Map

Map constructor with specified list of global element IDs for each
processor.  Arguments are:

     numGlobalElements  - Total number of elements over all processors.
                  Specify -1 to have the constructor compute
                  the number of global elements
     myGlobalElements   - A sequence of integers specifying the global
                  element indexes on this processor.
     indexBase          - The base integer value for indexed array
                  references.  Typically this is 0 for C/C++ and 1
                  for Fortran, but it can be set to any integer
                  value.
     comm               - The Epetra.Comm communicator. This communicator
                  can in turn be queried for processor rank and
                  size information.
__init__(Epetra_Map self, long long NumGlobalElements, int NumMyElements, long long const * MyGlobalElements, 
    int IndexBase, Comm Comm) -> Map

__init__(self, Map map) -> Map

Map copy constructor.

Epetra_Map::Epetra_Map(const Epetra_Map &map)

Epetra_Map copy constructor. 

Reimplemented from PyTrilinos.Epetra.BlockMap.

Reimplemented in PyTrilinos.Epetra.LocalMap.

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

• Epetra.py