Teko_InverseFactoryOperator.cpp

// @HEADER
// *****************************************************************************
//      Teko: A package for block and physics based preconditioning
//
// Copyright 2010 NTESS and the Teko contributors.
// SPDX-License-Identifier: BSD-3-Clause
// *****************************************************************************
// @HEADER

#include "Teko_InverseFactoryOperator.hpp"

// Teko includes
#include "Teko_BasicMappingStrategy.hpp"

// Thyra includes
#include "Thyra_EpetraLinearOp.hpp"

using Teuchos::RCP;
using Teuchos::rcp;
using Teuchos::rcp_dynamic_cast;
using Teuchos::rcpFromRef;

namespace Teko {
namespace Epetra {

InverseFactoryOperator::InverseFactoryOperator(const Teuchos::RCP<const InverseFactory>& ifp)
    : inverseFactory_(ifp), firstBuildComplete_(false), setConstFwdOp_(true) {}

void InverseFactoryOperator::initInverse(bool clearOld) {
  if (not clearOld) return;
  invOperator_ = Teuchos::null;
}

void InverseFactoryOperator::buildInverseOperator(const Teuchos::RCP<const Epetra_Operator>& A,
                                                  bool clear) {
  Teko_DEBUG_SCOPE("InverseFactoryOperator::buildInverseOperator", 10);

  // extract EpetraOperatorWrapper (throw on failure) and corresponding thyra operator
  RCP<const Thyra::LinearOpBase<double> > thyraA = extractLinearOp(A);

  // set the mapping strategy
  SetMapStrategy(rcp(new InverseMappingStrategy(extractMappingStrategy(A))));

  initInverse(clear);

  // actually build the inverse operator
  invOperator_ = Teko::buildInverse(*inverseFactory_, thyraA);

  SetOperator(invOperator_, false);

  firstBuildComplete_ = true;

  if (setConstFwdOp_) fwdOp_ = A;

  setConstFwdOp_ = true;

  TEUCHOS_ASSERT(invOperator_ != Teuchos::null);
  TEUCHOS_ASSERT(getForwardOp() != Teuchos::null);
  TEUCHOS_ASSERT(getThyraOp() != Teuchos::null);
  TEUCHOS_ASSERT(getMapStrategy() != Teuchos::null);
  TEUCHOS_ASSERT(firstBuildComplete_ == true);
}

void InverseFactoryOperator::buildInverseOperator(const Teuchos::RCP<Epetra_Operator>& A,
                                                  bool /* clear */) {
  setConstFwdOp_ = false;

  fwdOp_.initialize(A);

  buildInverseOperator(A.getConst());

  TEUCHOS_ASSERT(setConstFwdOp_ == true);
}

void InverseFactoryOperator::rebuildInverseOperator(const Teuchos::RCP<const Epetra_Operator>& A) {
  Teko_DEBUG_SCOPE("InverseFactoryOperator::rebuildPreconditioner", 10);

  // if the inverse hasn't been built yet, rebuild from scratch
  if (not firstBuildComplete_) {
    buildInverseOperator(A, false);
    return;
  }

  RCP<const Thyra::LinearOpBase<double> > thyraA = extractLinearOp(A);
  Teko::rebuildInverse(*inverseFactory_, thyraA, invOperator_);

  if (setConstFwdOp_) fwdOp_.initialize(A);

  SetOperator(invOperator_, false);

  setConstFwdOp_ = true;

  TEUCHOS_ASSERT(getForwardOp() != Teuchos::null);
  TEUCHOS_ASSERT(invOperator_ != Teuchos::null);
  TEUCHOS_ASSERT(getThyraOp() != Teuchos::null);
  TEUCHOS_ASSERT(firstBuildComplete_ == true);
}

void InverseFactoryOperator::rebuildInverseOperator(const Teuchos::RCP<Epetra_Operator>& A) {
  setConstFwdOp_ = false;

  fwdOp_.initialize(A);

  // build from constant epetra operator
  rebuildInverseOperator(A.getConst());

  TEUCHOS_ASSERT(setConstFwdOp_ == true);
}

Teuchos::RCP<const Thyra::LinearOpBase<double> > InverseFactoryOperator::extractLinearOp(
    const Teuchos::RCP<const Epetra_Operator>& A) const {
  // extract EpetraOperatorWrapper (throw on failure) and corresponding thyra operator
  const RCP<const EpetraOperatorWrapper>& eow = rcp_dynamic_cast<const EpetraOperatorWrapper>(A);

  // if it is an EpetraOperatorWrapper, then get the Thyra operator
  if (eow != Teuchos::null) return eow->getThyraOp();

  // otherwise wrap it up as a thyra operator
  return Thyra::epetraLinearOp(A);
}

Teuchos::RCP<const MappingStrategy> InverseFactoryOperator::extractMappingStrategy(
    const Teuchos::RCP<const Epetra_Operator>& A) const {
  // extract EpetraOperatorWrapper (throw on failure) and corresponding thyra operator
  const RCP<const EpetraOperatorWrapper>& eow = rcp_dynamic_cast<const EpetraOperatorWrapper>(A);

  // if it is an EpetraOperatorWrapper, then get the Thyra operator
  if (eow != Teuchos::null) return eow->getMapStrategy();

  // otherwise wrap it up as a thyra operator
  RCP<const Epetra_Map> range  = rcpFromRef(A->OperatorRangeMap());
  RCP<const Epetra_Map> domain = rcpFromRef(A->OperatorDomainMap());
  return rcp(new BasicMappingStrategy(range, domain, A->Comm()));
}

}  // end namespace Epetra
}  // end namespace Teko