Teuchos::Comm< Ordinal > Class Template Reference

Abstract interface class for a basic communication channel between one or more processes. More...

#include <Teuchos_Comm.hpp>

Inheritance diagram for Teuchos::Comm< Ordinal >:

List of all members.

Public Member Functions
Query functions
virtual int	getRank () const =0
	Returns the rank of this process.
virtual int	getSize () const =0
	Returns the number of processes that make up this communicator.
Collective Operations
virtual void	barrier () const =0
	Pause every process in *this communicator until all the processes reach this point.
virtual void	broadcast (const int rootRank, const Ordinal bytes, char buffer[]) const =0
	Broadcast values from the root process to the slave processes.
virtual void	gatherAll (const Ordinal sendBytes, const char sendBuffer[], const Ordinal recvBytes, char recvBuffer[]) const =0
	Gather values from each process to collect on all processes.
virtual void	reduceAll (const ValueTypeReductionOp< Ordinal, char > &reductOp, const Ordinal bytes, const char sendBuffer[], char globalReducts[]) const =0
	Global reduction.
virtual void	reduceAllAndScatter (const ValueTypeReductionOp< Ordinal, char > &reductOp, const Ordinal sendBytes, const char sendBuffer[], const Ordinal recvCounts[], const Ordinal blockSize, char myGlobalReducts[]) const =0
	Global reduction combined with a scatter.
virtual void	scan (const ValueTypeReductionOp< Ordinal, char > &reductOp, const Ordinal bytes, const char sendBuffer[], char scanReducts[]) const =0
	Scan reduction.
Point-to-Point Operations
virtual void	send (const Ordinal bytes, const char sendBuffer[], const int destRank) const =0
	Blocking send of data from this process to another process.
virtual int	receive (const int sourceRank, const Ordinal bytes, char recvBuffer[]) const =0
	Blocking receive of data from this process to another process.
Related Functions
(Note that these are not member functions.)
int	rank (const Comm< Ordinal > &comm)
	Get the process rank.
int	size (const Comm< Ordinal > &comm)
	Get the number of processes in the communicator.
void	barrier (const Comm< Ordinal > &comm)
	Barrier.
void	broadcast (const Comm< Ordinal > &comm, const int rootRank, const Ordinal count, Packet buffer[])
	Broadcast array of objects that use value semantics.
void	broadcast (const Comm< Ordinal > &comm, const int rootRank, Packet *object)
	Broadcast single object that use value semantics.
void	broadcast (const Comm< Ordinal > &comm, const Serializer< Ordinal, Packet > &serializer, const int rootRank, const Ordinal count, Packet *const buffer[])
	Broadcast array of objects that use reference semantics.
void	gatherAll (const Comm< Ordinal > &comm, const Ordinal sendCount, const Packet sendBuffer[], const Ordinal recvCount, Packet recvBuffer[])
	Gather array of objects that use value semantics from every process to every process.
void	gatherAll (const Comm< Ordinal > &comm, const Serializer< Ordinal, Packet > &serializer, const Ordinal sendCount, const Packet *const sendBuffer[], const Ordinal recvCount, Packet *const recvBuffer[])
	Gather array of objects that use reference semantics from every process to every process.
void	reduceAll (const Comm< Ordinal > &comm, const ValueTypeReductionOp< Ordinal, Packet > &reductOp, const Ordinal count, const Packet sendBuffer[], Packet globalReducts[])
	Collective reduce all of array of objects using value semantics using a user-defined reduction operator.
void	reduceAll (const Comm< Ordinal > &comm, const EReductionType reductType, const Ordinal count, const Packet sendBuffer[], Packet globalReducts[])
	Collective reduce all of array of objects using value semantics using a pre-defined reduction type.
void	reduceAll (const Comm< Ordinal > &comm, const EReductionType reductType, const Packet &send, Packet *globalReduct)
	Collective reduce all for single object using value semantics using a pre-defined reduction type.
void	reduceAll (const Comm< Ordinal > &comm, const Serializer< Ordinal, Packet > &serializer, const ReferenceTypeReductionOp< Ordinal, Packet > &reductOp, const Ordinal count, const Packet *const sendBuffer[], Packet *const globalReducts[])
	Collective reduce all for array of objects using reference semantics.
void	reduceAllAndScatter (const Comm< Ordinal > &comm, const ValueTypeReductionOp< Ordinal, Packet > &reductOp, const Ordinal sendCount, const Packet sendBuffer[], const Ordinal recvCounts[], Packet myGlobalReducts[])
	Reduce and Scatter array of objects that use value semantics using a user-defined reduction object.
void	reduceAllAndScatter (const Comm< Ordinal > &comm, const EReductionType reductType, const Ordinal sendCount, const Packet sendBuffer[], const Ordinal recvCounts[], Packet myGlobalReducts[])
	Reduce and Scatter array of objects that use value semantics using a a pre-defined reduction type.
void	reduceAllAndScatter (const Comm< Ordinal > &comm, const Serializer< Ordinal, Packet > &serializer, const ReferenceTypeReductionOp< Ordinal, Packet > &reductOp, const Ordinal sendCount, const Packet *const sendBuffer[], const Ordinal recvCounts[], Packet *const myGlobalReducts[])
	Reduce and Scatter array of objects that use reference semantics using a user-defined reduction object.
void	scan (const Comm< Ordinal > &comm, const ValueTypeReductionOp< Ordinal, Packet > &reductOp, const Ordinal count, const Packet sendBuffer[], Packet scanReducts[])
	Scan/Reduce array of objects that use value semantics using a user-defined reduction operator.
void	scan (const Comm< Ordinal > &comm, const EReductionType reductType, const Ordinal count, const Packet sendBuffer[], Packet scanReducts[])
	Scan/Reduce array of objects using value semantics using a predefined reduction type.
void	scan (const Comm< Ordinal > &comm, const EReductionType reductType, const Packet &send, Packet *scanReduct)
	Scan/Reduce single object using value semantics using a predefined reduction type.
void	scan (const Comm< Ordinal > &comm, const Serializer< Ordinal, Packet > &serializer, const ReferenceTypeReductionOp< Ordinal, Packet > &reductOp, const Ordinal count, const Packet *const sendBuffer[], Packet *const scanReducts[])
	Scan/Reduce array of objects that use reference semantics using a user-defined reduction operator.
void	send (const Comm< Ordinal > &comm, const Ordinal count, const Packet sendBuffer[], const int destRank)
	Send objects that use values semantics to another process.
void	send (const Comm< Ordinal > &comm, const Packet &send, const int destRank)
	Send a single object that use values semantics to another process.
void	send (const Comm< Ordinal > &comm, const Serializer< Ordinal, Packet > &serializer, const Ordinal count, const Packet *const sendBuffer[], const int destRank)
	Send objects that use reference semantics to another process.
int	receive (const Comm< Ordinal > &comm, const int sourceRank, const Ordinal count, Packet recvBuffer[])
	Receive objects that use values semantics from another process.
int	receive (const Comm< Ordinal > &comm, const int sourceRank, Packet *recv)
	Receive a single object that use values semantics from another process.
int	receive (const Comm< Ordinal > &comm, const Serializer< Ordinal, Packet > &serializer, const int sourceRank, const Ordinal count, Packet *const recvBuffer[])
	Receive objects that use reference semantics from another process.

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Detailed Description

template<typename Ordinal>
class Teuchos::Comm< Ordinal >

Abstract interface class for a basic communication channel between one or more processes.

This interface is templated on the ordinal type but only deals with buffers of untyped data represented as arrays char type. All reduction operations that are initiated by the concreate communicator object are performed by user-defined ReductOpBase objects. It is the responsibility of the ReductOpBase object to know what the currect data type is, to perform casts or serializations/unserializations to and from char[] buffers, and to know how to reduce the objects correctly. It is strictly up to the client to correctly convert data types to char[] arrays but there is a great deal of helper code to make this easy and safe.

ToDo: Finish documentation!

Definition at line 53 of file Teuchos_Comm.hpp.

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Member Function Documentation

template<typename Ordinal> virtual int Teuchos::Comm< Ordinal >::getRank (   )  const [pure virtual]

Returns the rank of this process. Postconditions: 0 <= return && return < this->getSize() Implemented in Teuchos::MpiComm< Ordinal >, and Teuchos::SerialComm< Ordinal >.

template<typename Ordinal> virtual int Teuchos::Comm< Ordinal >::getSize (   )  const [pure virtual]

Returns the number of processes that make up this communicator. Postconditions: return > 0 Implemented in Teuchos::MpiComm< Ordinal >, and Teuchos::SerialComm< Ordinal >.

template<typename Ordinal> virtual void Teuchos::Comm< Ordinal >::barrier (   )  const [pure virtual]

Pause every process in *this communicator until all the processes reach this point. Implemented in Teuchos::MpiComm< Ordinal >, and Teuchos::SerialComm< Ordinal >.

template<typename Ordinal> virtual void Teuchos::Comm< Ordinal >::broadcast (  const int  rootRank, const Ordinal  bytes, char  buffer[] )  const [pure virtual]

Broadcast values from the root process to the slave processes. Parameters: rootRank  [in] The rank of the root process. count  [in] The number of bytes in buffer[]. buffer  [in/out] Array (length bytes) of packed data. Must be set on input on the root processes with rank root. On output, each processs, including the root process contains the data. Preconditions: 0 <= rootRank && rootRank < this->getSize() Implemented in Teuchos::MpiComm< Ordinal >, and Teuchos::SerialComm< Ordinal >.

template<typename Ordinal> virtual void Teuchos::Comm< Ordinal >::gatherAll (  const Ordinal  sendBytes, const char  sendBuffer[], const Ordinal  recvBytes, char  recvBuffer[] )  const [pure virtual]

Gather values from each process to collect on all processes. Parameters: sendBytes  [in] Number of entires in sendBuffer[] on input. sendBuffer  [in] Array (length sendBytes) of data being sent from each process. recvBytes  [in] Number of entires in recvBuffer[] which must be equal to sendBytes*this->getSize(). This field is just here for debug checking. recvBuffer  [out] Array (length recvBytes) of all of the entires sent from each processes. Specifically, recvBuffer[sendBytes*j+i], for j=0...this->getSize()-1 and i=0...sendBytes-1, is the entry sendBuffer[i] from process with rank j. Preconditions: recvBytes==sendBytes*this->getSize() Implemented in Teuchos::MpiComm< Ordinal >, and Teuchos::SerialComm< Ordinal >.

template<typename Ordinal> virtual void Teuchos::Comm< Ordinal >::reduceAll (  const ValueTypeReductionOp< Ordinal, char > &  reductOp, const Ordinal  bytes, const char  sendBuffer[], char  globalReducts[] )  const [pure virtual]

Global reduction. Parameters: reductOp  [in] The user-defined reduction operation bytes  [in] The length of the buffers sendBuffer[] and globalReducts[]. sendBuffer  [in] Array (length bytes) of the data contributed from each process. globalReducts  [out] Array (length bytes) of the global reduction from each process. Implemented in Teuchos::MpiComm< Ordinal >, and Teuchos::SerialComm< Ordinal >.

template<typename Ordinal> virtual void Teuchos::Comm< Ordinal >::reduceAllAndScatter (  const ValueTypeReductionOp< Ordinal, char > &  reductOp, const Ordinal  sendBytes, const char  sendBuffer[], const Ordinal  recvCounts[], const Ordinal  blockSize, char  myGlobalReducts[] )  const [pure virtual]

Global reduction combined with a scatter. Parameters: reductOp  [in] The user-defined reduction operation. sendBytes  [in] The number of entires in sendBuffer[]. This must be the same in each process. sendBuffer  [in] Array (length sendBytes) of the data contributed from each process. recvCounts  [in] Array (length this->getSize()) which gives the number of element blocks of block size blockSize from the global reduction that will be recieved in each process. blockSize  [in] Gives the block size for interpreting recvCount myGlobalReducts  [out] Array (length blockSize*recvBytes[rank]) of the global reductions gathered in this process. Preconditions: sendBytes == blockSize*sum(recvCounts[i],i=0...this->getSize()-1) Implemented in Teuchos::MpiComm< Ordinal >, and Teuchos::SerialComm< Ordinal >.

template<typename Ordinal> virtual void Teuchos::Comm< Ordinal >::scan (  const ValueTypeReductionOp< Ordinal, char > &  reductOp, const Ordinal  bytes, const char  sendBuffer[], char  scanReducts[] )  const [pure virtual]

Scan reduction. Parameters: reductOp  [in] The user-defined reduction operation bytes  [in] The length of the buffers sendBuffer[] and scanReducts[]. sendBuffer  [in] Array (length bytes) of the data contributed from each process. scanReducts  [out] Array (length bytes) of the reduction up to and including this process. Implemented in Teuchos::MpiComm< Ordinal >, and Teuchos::SerialComm< Ordinal >.

template<typename Ordinal> virtual void Teuchos::Comm< Ordinal >::send (  const Ordinal  bytes, const char  sendBuffer[], const int  destRank )  const [pure virtual]

Blocking send of data from this process to another process. Parameters: bytes  [in] The number of bytes of data being passed between processes. sendBuffer  [in] Array (length bytes) of data being sent from this process. This buffer can be immediately destroyed or reused as soon as the function exits (that is why this function is "blocking"). destRank  [in] The rank of the process to recieve the data. Preconditions: 0 <= destRank && destRank < this->getSize() destRank != this->getRank() Implemented in Teuchos::MpiComm< Ordinal >, and Teuchos::SerialComm< Ordinal >.

template<typename Ordinal> virtual int Teuchos::Comm< Ordinal >::receive (  const int  sourceRank, const Ordinal  bytes, char  recvBuffer[] )  const [pure virtual]

Blocking receive of data from this process to another process. Parameters: sourceRank  [in] The rank of the process to recieve the data from. If sourceRank < 0 then data will be recieved from any process. bytes  [in] The number of bytes of data being passed between processes. recvBuffer  [out] Array (length bytes) of data being received from this process. This buffer can be immediately used to access the data as soon as the function exits (that is why this function is "blocking"). Preconditions: [sourceRank >= 0] sourceRank < this->getSize() sourceRank != this->getRank() Returns: Returns the senders rank. Implemented in Teuchos::MpiComm< Ordinal >, and Teuchos::SerialComm< Ordinal >.

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Friends And Related Function Documentation

template<typename Ordinal> int rank (  const Comm< Ordinal > &  comm  )  [related]

Get the process rank.

template<typename Ordinal> int size (  const Comm< Ordinal > &  comm  )  [related]

Get the number of processes in the communicator.

template<typename Ordinal> void barrier (  const Comm< Ordinal > &  comm  )  [related]

Barrier.

template<typename Ordinal> void broadcast (  const Comm< Ordinal > &  comm, const int  rootRank, const Ordinal  count, Packet  buffer[] )  [related]

Broadcast array of objects that use value semantics.

template<typename Ordinal> void broadcast (  const Comm< Ordinal > &  comm, const int  rootRank, Packet *  object )  [related]

Broadcast single object that use value semantics.

template<typename Ordinal> void broadcast (  const Comm< Ordinal > &  comm, const Serializer< Ordinal, Packet > &  serializer, const int  rootRank, const Ordinal  count, Packet *const   buffer[] )  [related]

Broadcast array of objects that use reference semantics.

template<typename Ordinal> void gatherAll (  const Comm< Ordinal > &  comm, const Ordinal  sendCount, const Packet  sendBuffer[], const Ordinal  recvCount, Packet  recvBuffer[] )  [related]

Gather array of objects that use value semantics from every process to every process.

template<typename Ordinal> void gatherAll (  const Comm< Ordinal > &  comm, const Serializer< Ordinal, Packet > &  serializer, const Ordinal  sendCount, const Packet *const   sendBuffer[], const Ordinal  recvCount, Packet *const   recvBuffer[] )  [related]

Gather array of objects that use reference semantics from every process to every process.

template<typename Ordinal> void reduceAll (  const Comm< Ordinal > &  comm, const ValueTypeReductionOp< Ordinal, Packet > &  reductOp, const Ordinal  count, const Packet  sendBuffer[], Packet  globalReducts[] )  [related]

Collective reduce all of array of objects using value semantics using a user-defined reduction operator.

template<typename Ordinal> void reduceAll (  const Comm< Ordinal > &  comm, const EReductionType  reductType, const Ordinal  count, const Packet  sendBuffer[], Packet  globalReducts[] )  [related]

Collective reduce all of array of objects using value semantics using a pre-defined reduction type.

template<typename Ordinal> void reduceAll (  const Comm< Ordinal > &  comm, const EReductionType  reductType, const Packet &  send, Packet *  globalReduct )  [related]

Collective reduce all for single object using value semantics using a pre-defined reduction type.

template<typename Ordinal> void reduceAll (  const Comm< Ordinal > &  comm, const Serializer< Ordinal, Packet > &  serializer, const ReferenceTypeReductionOp< Ordinal, Packet > &  reductOp, const Ordinal  count, const Packet *const   sendBuffer[], Packet *const   globalReducts[] )  [related]

Collective reduce all for array of objects using reference semantics.

template<typename Ordinal> void reduceAllAndScatter (  const Comm< Ordinal > &  comm, const ValueTypeReductionOp< Ordinal, Packet > &  reductOp, const Ordinal  sendCount, const Packet  sendBuffer[], const Ordinal  recvCounts[], Packet  myGlobalReducts[] )  [related]

Reduce and Scatter array of objects that use value semantics using a user-defined reduction object.

template<typename Ordinal> void reduceAllAndScatter (  const Comm< Ordinal > &  comm, const EReductionType  reductType, const Ordinal  sendCount, const Packet  sendBuffer[], const Ordinal  recvCounts[], Packet  myGlobalReducts[] )  [related]

Reduce and Scatter array of objects that use value semantics using a a pre-defined reduction type.

template<typename Ordinal> void reduceAllAndScatter (  const Comm< Ordinal > &  comm, const Serializer< Ordinal, Packet > &  serializer, const ReferenceTypeReductionOp< Ordinal, Packet > &  reductOp, const Ordinal  sendCount, const Packet *const   sendBuffer[], const Ordinal  recvCounts[], Packet *const   myGlobalReducts[] )  [related]

Reduce and Scatter array of objects that use reference semantics using a user-defined reduction object.

template<typename Ordinal> void scan (  const Comm< Ordinal > &  comm, const ValueTypeReductionOp< Ordinal, Packet > &  reductOp, const Ordinal  count, const Packet  sendBuffer[], Packet  scanReducts[] )  [related]

Scan/Reduce array of objects that use value semantics using a user-defined reduction operator.

template<typename Ordinal> void scan (  const Comm< Ordinal > &  comm, const EReductionType  reductType, const Ordinal  count, const Packet  sendBuffer[], Packet  scanReducts[] )  [related]

Scan/Reduce array of objects using value semantics using a predefined reduction type.

template<typename Ordinal> void scan (  const Comm< Ordinal > &  comm, const EReductionType  reductType, const Packet &  send, Packet *  scanReduct )  [related]

Scan/Reduce single object using value semantics using a predefined reduction type.

template<typename Ordinal> void scan (  const Comm< Ordinal > &  comm, const Serializer< Ordinal, Packet > &  serializer, const ReferenceTypeReductionOp< Ordinal, Packet > &  reductOp, const Ordinal  count, const Packet *const   sendBuffer[], Packet *const   scanReducts[] )  [related]

Scan/Reduce array of objects that use reference semantics using a user-defined reduction operator.

template<typename Ordinal> void send (  const Comm< Ordinal > &  comm, const Ordinal  count, const Packet  sendBuffer[], const int  destRank )  [related]

Send objects that use values semantics to another process.

template<typename Ordinal> void send (  const Comm< Ordinal > &  comm, const Packet &  send, const int  destRank )  [related]

Send a single object that use values semantics to another process.

template<typename Ordinal> void send (  const Comm< Ordinal > &  comm, const Serializer< Ordinal, Packet > &  serializer, const Ordinal  count, const Packet *const   sendBuffer[], const int  destRank )  [related]

Send objects that use reference semantics to another process.

template<typename Ordinal> int receive (  const Comm< Ordinal > &  comm, const int  sourceRank, const Ordinal  count, Packet  recvBuffer[] )  [related]

Receive objects that use values semantics from another process.

template<typename Ordinal> int receive (  const Comm< Ordinal > &  comm, const int  sourceRank, Packet *  recv )  [related]

Receive a single object that use values semantics from another process.

template<typename Ordinal> int receive (  const Comm< Ordinal > &  comm, const Serializer< Ordinal, Packet > &  serializer, const int  sourceRank, const Ordinal  count, Packet *const   recvBuffer[] )  [related]

Receive objects that use reference semantics from another process.

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

• Teuchos_Comm.hpp
• Teuchos_CommHelpers.hpp

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