# NOX::Abstract::Group Class Reference

NOX pure abstract interface to a "group"; i.e., a solution vector and the corresponding F-vector, Jacobian matrix, gradient vector, and Newton vector. More...

#include <NOX_Abstract_Group.H>

Inheritance diagram for NOX::Abstract::Group:

[legend]
List of all members.

## Public Types

enum  ReturnType {
Failed
}
The computation of, say, the Newton direction in computeNewton() may fail in many different ways, so we have included a variety of return codes to describe the failures. Of course, we also have a code for success. More...

## Public Member Functions

Group ()
Constructor.
virtual ~Group ()
Destructor.
virtual NOX::Abstract::Groupoperator= (const NOX::Abstract::Group &source)=0
Copies the source group into this group.
"Compute" functions.
virtual void setX (const NOX::Abstract::Vector &y)=0
Set the solution vector x to y.
virtual void computeX (const NOX::Abstract::Group &grp, const NOX::Abstract::Vector &d, double step)=0
Compute x = grp.x + step * d.
virtual NOX::Abstract::Group::ReturnType computeF ()=0
Compute and store F(x).
virtual NOX::Abstract::Group::ReturnType computeJacobian ()
Compute and store Jacobian.
virtual NOX::Abstract::Group::ReturnType computeNewton (Teuchos::ParameterList &params)
Compute the Newton direction, using parameters for the linear solve.
Jacobian operations.
Operations using the Jacobian matrix.

virtual NOX::Abstract::Group::ReturnType applyJacobian (const NOX::Abstract::Vector &input, NOX::Abstract::Vector &result) const
Applies Jacobian to the given input vector and puts the answer in the result.
virtual NOX::Abstract::Group::ReturnType applyJacobianTranspose (const NOX::Abstract::Vector &input, NOX::Abstract::Vector &result) const
Applies Jacobian-Transpose to the given input vector and puts the answer in the result.
virtual NOX::Abstract::Group::ReturnType applyJacobianInverse (Teuchos::ParameterList &params, const NOX::Abstract::Vector &input, NOX::Abstract::Vector &result) const
Applies the inverse of the Jacobian matrix to the given input vector and puts the answer in result.
virtual NOX::Abstract::Group::ReturnType applyRightPreconditioning (bool useTranspose, Teuchos::ParameterList &params, const NOX::Abstract::Vector &input, NOX::Abstract::Vector &result) const
Apply right preconditiong to the given input vector.
Block Jacobian operations.
Operations using the Jacobian matrix.

virtual NOX::Abstract::Group::ReturnType applyJacobianMultiVector (const NOX::Abstract::MultiVector &input, NOX::Abstract::MultiVector &result) const
applyJacobian for multiple right-hand sides
virtual NOX::Abstract::Group::ReturnType applyJacobianTransposeMultiVector (const NOX::Abstract::MultiVector &input, NOX::Abstract::MultiVector &result) const
applyJacobianTranspose for multiple right-hand sides
virtual NOX::Abstract::Group::ReturnType applyJacobianInverseMultiVector (Teuchos::ParameterList &params, const NOX::Abstract::MultiVector &input, NOX::Abstract::MultiVector &result) const
applyJacobianInverse for multiple right-hand sides
virtual NOX::Abstract::Group::ReturnType applyRightPreconditioningMultiVector (bool useTranspose, Teuchos::ParameterList &params, const NOX::Abstract::MultiVector &input, NOX::Abstract::MultiVector &result) const
applyRightPreconditioning for multiple right-hand sides
"Is" functions.
Checks to see if various objects have been computed. Returns true if the corresponding "compute" function has been called since the last change to the solution vector.

virtual bool isF () const =0
Return true if F is valid.
virtual bool isJacobian () const
Return true if the Jacobian is valid.
Return true if the gradient is valid.
virtual bool isNewton () const
Return true if the Newton direction is valid.
"Get" functions.
Note that these function do not check whether or not the vectors are valid. Must use the "Is" functions for that purpose.

virtual const NOX::Abstract::VectorgetX () const =0
Return solution vector.
virtual const NOX::Abstract::VectorgetF () const =0
Return F(x).
virtual double getNormF () const =0
Return 2-norm of F(x).
virtual const NOX::Abstract::VectorgetGradient () const =0
virtual const NOX::Abstract::VectorgetNewton () const =0
Return Newton direction.
virtual NOX::Abstract::Group::ReturnType getNormLastLinearSolveResidual (double &residual) const
Return the norm of the last linear solve residual as the result of either a call to computeNewton() or applyJacobianInverse().
Creating new Groups.
virtual Teuchos::RefCountPtr<
NOX::Abstract::Group
clone (NOX::CopyType type=NOX::DeepCopy) const =0
Create a new Group of the same derived type as this one by cloning this one, and return a ref count pointer to the new group.

## Detailed Description

NOX pure abstract interface to a "group"; i.e., a solution vector and the corresponding F-vector, Jacobian matrix, gradient vector, and Newton vector.

This class is a member of the namespace NOX::Abstract.

The user should implement their own concrete implementation of this class or use one of the implementations provided by us. Typically the implementation is also tied to a particular NOX::Abstract::Vector implementation.

Note:
The group may be implemented so that multiple groups can share underlying memory space. This is particularly important when it comes to the Jacobian, which is often to big to be replicated for every group. Thus, we have included instructions on how shared data should be treated for the operator=() and clone() functions.

## Member Enumeration Documentation

The computation of, say, the Newton direction in computeNewton() may fail in many different ways, so we have included a variety of return codes to describe the failures. Of course, we also have a code for success.

Note:
These return types may be expanded in future releases.
Enumeration values:
 Ok Computation completed successfully. NotDefined This function is not implemented. BadDependency Data dependencies not satisfied. NotConverged Unable to satisfy convergence criteria. Failed Any other type of failure.

## Constructor & Destructor Documentation

 NOX::Abstract::Group::Group ( ) [inline]
 Constructor. Note:Constructors for any derived object should always define a default x-value so that getX() is always defined.

## Member Function Documentation

 NOX::Abstract::Group::ReturnType NOX::Abstract::Group::applyJacobian ( const NOX::Abstract::Vector & input, NOX::Abstract::Vector & result ) const [virtual]
 Applies Jacobian to the given input vector and puts the answer in the result. Computes where is the Jacobian, is the input vector, and is the result vector. Returns: NOX::Abstract::Group::NotDefined - Returned by default implementation in NOX::Abstract::Group NOX::Abstract::Group::BadDependency - If the Jacobian has not been computed NOX::Abstract::Group::Failed - If the computation fails NOX::Abstract::Group::Ok - Otherwise

 NOX::Abstract::Group::ReturnType NOX::Abstract::Group::applyJacobianInverse ( Teuchos::ParameterList & params, const NOX::Abstract::Vector & input, NOX::Abstract::Vector & result ) const [virtual]
 Applies the inverse of the Jacobian matrix to the given input vector and puts the answer in result. Computes where is the Jacobian, is the input vector, and is the result vector. The "Tolerance" parameter specifies that the solution should be such that Returns: NOX::Abstract::Group::NotDefined - Returned by default implementation in NOX::Abstract::Group NOX::Abstract::Group::BadDependency - If has not been computed NOX::Abstract::Group::NotConverged - If the linear solve fails to satisfy the "Tolerance" specified in params NOX::Abstract::Group::Failed - If the computation fails NOX::Abstract::Group::Ok - Otherwise The parameter "Tolerance" may be added/modified in the list of parameters - this is the ideal solution tolerance for an iterative linear solve.

 NOX::Abstract::Group::ReturnType NOX::Abstract::Group::applyJacobianInverseMultiVector ( Teuchos::ParameterList & params, const NOX::Abstract::MultiVector & input, NOX::Abstract::MultiVector & result ) const [virtual]
 applyJacobianInverse for multiple right-hand sides The default implementation here calls applyJacobianInverse() for each right hand side serially but should be overloaded if a block solver is available.

 NOX::Abstract::Group::ReturnType NOX::Abstract::Group::applyJacobianMultiVector ( const NOX::Abstract::MultiVector & input, NOX::Abstract::MultiVector & result ) const [virtual]
 applyJacobian for multiple right-hand sides The default implementation here calls applyJacobian() for each right hand side serially but should be overloaded if a block method is available.

 NOX::Abstract::Group::ReturnType NOX::Abstract::Group::applyJacobianTranspose ( const NOX::Abstract::Vector & input, NOX::Abstract::Vector & result ) const [virtual]
 Applies Jacobian-Transpose to the given input vector and puts the answer in the result. Computes where is the Jacobian, is the input vector, and is the result vector. Returns: NOX::Abstract::Group::NotDefined - Returned by default implementation in NOX::Abstract::Group NOX::Abstract::Group::BadDependency - If has not been computed NOX::Abstract::Group::Failed - If the computation fails NOX::Abstract::Group::Ok - Otherwise

 NOX::Abstract::Group::ReturnType NOX::Abstract::Group::applyJacobianTransposeMultiVector ( const NOX::Abstract::MultiVector & input, NOX::Abstract::MultiVector & result ) const [virtual]
 applyJacobianTranspose for multiple right-hand sides The default implementation here calls applyJacobianTranspose() for each right hand side serially but should be overloaded if a block method is available.

 NOX::Abstract::Group::ReturnType NOX::Abstract::Group::applyRightPreconditioning ( bool useTranspose, Teuchos::ParameterList & params, const NOX::Abstract::Vector & input, NOX::Abstract::Vector & result ) const [virtual]
 Apply right preconditiong to the given input vector. Let be a right preconditioner for the Jacobian ; in other words, is a matrix such that Compute where is the input vector and is the result vector. If useTranspose is true, then the transpose of the preconditioner is applied: The transpose preconditioner is currently only required for Tensor methods. The "Tolerance" parameter specifies that the solution should be such that Returns: NOX::Abstract::Group::NotDefined - Returned by default implementation in NOX::Abstract::Group NOX::Abstract::Group::NotConverged - If the linear solve fails to satisfy the "Tolerance" specified in params NOX::Abstract::Group::Failed - If the computation fails NOX::Abstract::Group::Ok - Otherwise The parameters are from the "Linear %Solver" sublist of the "Direction" sublist that is passed to solver during construction. Reimplemented in NOX::Epetra::Group.

 NOX::Abstract::Group::ReturnType NOX::Abstract::Group::applyRightPreconditioningMultiVector ( bool useTranspose, Teuchos::ParameterList & params, const NOX::Abstract::MultiVector & input, NOX::Abstract::MultiVector & result ) const [virtual]
 applyRightPreconditioning for multiple right-hand sides The default implementation here calls applyRightPreconditioning() for each right hand side serially but should be overloaded if a block method is available.

 virtual Teuchos::RefCountPtr NOX::Abstract::Group::clone ( NOX::CopyType type = NOX::DeepCopy ) const [pure virtual]
 Create a new Group of the same derived type as this one by cloning this one, and return a ref count pointer to the new group. If type is NOX::DeepCopy, then we need to create an exact replica of "this". Otherwise, if type is NOX::ShapeCopy, we need only replicate the shape of "this" (only the memory is allocated, the values are not copied into the vectors and Jacobian). Returns NULL if clone is not supported. Note:Any shared data should have its ownership transfered to this group from the source for a NOX::DeepCopy.

 virtual NOX::Abstract::Group::ReturnType NOX::Abstract::Group::computeF ( ) [pure virtual]
 Compute and store F(x). Note:It's generally useful to also compute and store the 2-norm of F(x) at this point for later access by the getNormF() function. Returns: NOX::Abstract::Group::Failed - If the computation fails in any way NOX::Abstract::Group::Ok - Otherwise

 Compute and store gradient. We can pose the nonlinear equation problem as an optimization problem as follows: In that case, the gradient (of ) is defined as Returns: NOX::Abstract::Group::NotDefined - Returned by default implementation in NOX::Abstract::Group NOX::Abstract::Group::BadDependency - If either or has not been computed NOX::Abstract::Group::Failed - If the computation fails in any other way NOX::Abstract::Group::Ok - Otherwise

 NOX::Abstract::Group::ReturnType NOX::Abstract::Group::computeJacobian ( ) [virtual]
 Compute and store Jacobian. Recall that The Jacobian is denoted by and defined by Note:If this is a shared object, this group should taken ownership of the Jacobian before it computes it. Returns: NOX::Abstract::Group::NotDefined - Returned by default implementation in NOX::Abstract::Group NOX::Abstract::Group::Failed - If the computation fails in any other way NOX::Abstract::Group::Ok - Otherwise

 NOX::Abstract::Group::ReturnType NOX::Abstract::Group::computeNewton ( Teuchos::ParameterList & params ) [virtual]
 Compute the Newton direction, using parameters for the linear solve. The Newton direction is the solution, s, of The parameters are from the "Linear %Solver" sublist of the "Direction" sublist that is passed to solver during construction. The "Tolerance" parameter may be added/modified in the sublist of "Linear Solver" parameters that is passed into this function. The solution should be such that Returns: NOX::Abstract::Group::NotDefined - Returned by default implementation in NOX::Abstract::Group NOX::Abstract::Group::BadDependency - If either or has not been computed NOX::Abstract::Group::NotConverged - If the linear solve fails to satisfy the "Tolerance" specified in params NOX::Abstract::Group::Failed - If the computation fails in any other way NOX::Abstract::Group::Ok - Otherwise

 virtual void NOX::Abstract::Group::computeX ( const NOX::Abstract::Group & grp, const NOX::Abstract::Vector & d, double step ) [pure virtual]
 Compute x = grp.x + step * d. Let denote this group's solution vector. Let denote the result of grp.getX(). Then set Note:This should invalidate the function value, Jacobian, gradient, and Newton direction. Throw an error if the copy fails. Returns:Reference to this object

 virtual double NOX::Abstract::Group::getNormF ( ) const [pure virtual]

 NOX::Abstract::Group::ReturnType NOX::Abstract::Group::getNormLastLinearSolveResidual ( double & residual ) const [virtual]
 Return the norm of the last linear solve residual as the result of either a call to computeNewton() or applyJacobianInverse(). Returns: NOX::Abstract::Group::NotDefined - Returned by default implementation in NOX::Abstract::Group NOX::Abstract::Group::BadDependency - If no linear solve has been calculated NOX::Abstract::Group::Failed - Any other type of failure NOX::Abstract::Group::Ok - Otherwise Reimplemented in NOX::Epetra::Group.

 bool NOX::Abstract::Group::isGradient ( ) const [virtual]
 Return true if the gradient is valid. Note:Default implementation in NOX::Abstract::Group returns false.

 bool NOX::Abstract::Group::isJacobian ( ) const [virtual]
 Return true if the Jacobian is valid. Note:Default implementation in NOX::Abstract::Group returns false.

 bool NOX::Abstract::Group::isNewton ( ) const [virtual]
 Return true if the Newton direction is valid. Note:Default implementation in NOX::Abstract::Group returns false.

 virtual NOX::Abstract::Group& NOX::Abstract::Group::operator= ( const NOX::Abstract::Group & source ) [pure virtual]
 Copies the source group into this group. Note:Any shared data owned by the source should have its ownership transfered to this group. This may result in a secret modification to the source object.

 virtual void NOX::Abstract::Group::setX ( const NOX::Abstract::Vector & y ) [pure virtual]
 Set the solution vector x to y. Note:This should invalidate the function value, Jacobian, gradient, and Newton direction. Throw an error if the copy fails. Returns:Reference to this object

The documentation for this class was generated from the following files:
• NOX_Abstract_Group.H
• NOX_Abstract_Group.C

Generated on Thu Sep 18 12:38:37 2008 for NOX by  1.3.9.1