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Base abstract VectorSpaceBase
class for all SPMDbased vector spaces.
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#include <Thyra_SpmdVectorSpaceBase_decl.hpp>
Pure virtual methods to be overridden by subclasses  
virtual Teuchos::RCP< const Teuchos::Comm< Ordinal > >  getComm () const =0 
Returns the SPMD communicator.  
virtual Ordinal  localSubDim () const =0 
Returns the number of local elements stored on this process.  
virtual Ordinal  localOffset () const =0 
Returns the offset for the local subvector stored on this process.  
virtual Ordinal  mapCode () const =0 
Returns the code for the mapping of elements to processes. 
Base abstract VectorSpaceBase
class for all SPMDbased vector spaces.
This interface defines a basic mechanism for the interoperability of SPMD VectorBase
and MultiVectorBase
objects. See the base classes SPMDVetorBase
and SpmdMultiVectorBase
to demonstrate how this interface is used to achieve universal interoperability of vector and multivector objects.
Specifically, these classes are designed to handle three different use case:
localSubDim()==dim()
. In this case, the SPMD_Comm
returned from getComm()
can be SPMD_COMM_NULL
. localSubDim() < dim()
. This implementation assumes that all of the elements are stored contiguously in each process and that there are no ghost elements as described below. localSubDim()==dim()
even if there is more than one process. This case is checked for so that the reduction operations are performed correctly. This interface provides all the information necessary to implement the SpmdVectorBase::applyOp()
and SpmdMultiVectorBase::applyOp()
functions in all of the above described use cases. This interface returns an SPMD communicator (of which all compatible vector spaces must have the same communicator obviously) through the method getComm()
.
For the case of a distributed parallel vector, this interface base class assumes that vector data is partitioned to processes in contiguous chunks of dense subvectors. To spell this out, let v
be the local vector that is sorted on this process and let g
be the global vector. Then these two vectors are related (using zerobased indexing) as:
v(k) == g(this>localOffset() + k), for k = 0...this>localSubDim()1
Any type of mapping of vector data to processes that can not be interpreted in this way can not rely on this base class for interoperability. Note that as long as the elements in a process are partitioned to unique processes and no ghost elements are present, the actual indexes used by the application with these vectors is immaterial. The indexes associated with this set of interfaces, however, are only meaningful to abstract numerical algorithms and provide an arbitrary label for certain types of coordinatedependent operations (like required in an activeset method for optimization). Therefore, as long as the underlying vector represents a unique partitioning of elements, these classes can be used. There is a default implementation of localOffset()
that automatically assumes this contiguous mapping of elements to processes and in general this should not be changed.
Notes to subclass developers:
The pure virtual methods getComm()
and localSubDim()
declared in this interface along with the pure virtual methods dim()
and createMember()
are the only methods that must be overridden.
If this
this is in an uninitialized state then localSubDim()
should return 0
.
If optimized implementations of multivectors can be supported, then the createMembers()
method should also be overridden.
Definition at line 132 of file Thyra_SpmdVectorSpaceBase_decl.hpp.
virtual Teuchos::RCP<const Teuchos::Comm<Ordinal> > Thyra::SpmdVectorSpaceBase< Scalar >::getComm  (  )  const [pure virtual] 
Returns the SPMD communicator.
Implemented in Thyra::DefaultSpmdVectorSpace< Scalar >, and Thyra::TpetraVectorSpace< Scalar, LocalOrdinal, GlobalOrdinal, Node >.
virtual Ordinal Thyra::SpmdVectorSpaceBase< Scalar >::localSubDim  (  )  const [pure virtual] 
Returns the number of local elements stored on this process.
If this
this is uninitialized then localSubDim()
returns 0
.
Implemented in Thyra::DefaultSpmdVectorSpace< Scalar >, and Thyra::TpetraVectorSpace< Scalar, LocalOrdinal, GlobalOrdinal, Node >.
virtual Ordinal Thyra::SpmdVectorSpaceBase< Scalar >::localOffset  (  )  const [pure virtual] 
Returns the offset for the local subvector stored on this process.
Implemented in Thyra::SpmdVectorSpaceDefaultBase< Scalar >.
virtual Ordinal Thyra::SpmdVectorSpaceBase< Scalar >::mapCode  (  )  const [pure virtual] 
Returns the code for the mapping of elements to processes.
Postconditions:
this>localSubDim() > 0
] this>mapCode() > 0
. this>localSubDim() <= 0
] this>mapCode() <= 0
. Implemented in Thyra::SpmdVectorSpaceDefaultBase< Scalar >.