The Incomplete Cholesky (IC) preconditioner solves the equation 
#include <ginkgo/core/preconditioner/ic.hpp>
Classes | |
| class | Factory |
| struct | parameters_type |
Public Types | |
| using | value_type = typename LSolverType::value_type |
| using | l_solver_type = LSolverType |
| using | lh_solver_type = typename LSolverType::transposed_type |
| using | index_type = IndexType |
| using | transposed_type = Ic<LSolverType, IndexType> |
Public Types inherited from gko::EnablePolymorphicAssignment< Ic< solver::LowerTrs<>, int32 > > | |
| using | result_type |
Public Types inherited from gko::ConvertibleTo< Ic< solver::LowerTrs<>, int32 > > | |
| using | result_type |
Public Member Functions | |
| const parameters_type & | get_parameters () const |
| std::shared_ptr< const l_solver_type > | get_l_solver () const |
| Returns the solver which is used for the provided L matrix. | |
| std::shared_ptr< const lh_solver_type > | get_lh_solver () const |
| Returns the solver which is used for the L^H matrix. | |
| std::unique_ptr< LinOp > | transpose () const override |
| Returns a LinOp representing the transpose of the Transposable object. | |
| std::unique_ptr< LinOp > | conj_transpose () const override |
| Returns a LinOp representing the conjugate transpose of the Transposable object. | |
| Ic & | operator= (const Ic &other) |
| Copy-assigns an IC preconditioner. | |
| Ic & | operator= (Ic &&other) |
| Move-assigns an IC preconditioner. | |
| Ic (const Ic &other) | |
| Copy-constructs an IC preconditioner. | |
| Ic (Ic &&other) | |
| Move-constructs an IC preconditioner. | |
Public Member Functions inherited from gko::EnableLinOp< Ic< solver::LowerTrs<>, int32 > > | |
| const Ic< solver::LowerTrs<>, int32 > * | apply (ptr_param< const LinOp > b, ptr_param< LinOp > x) const |
| Ic< solver::LowerTrs<>, int32 > * | apply (ptr_param< const LinOp > b, ptr_param< LinOp > x) |
| const Ic< solver::LowerTrs<>, int32 > * | apply (ptr_param< const LinOp > alpha, ptr_param< const LinOp > b, ptr_param< const LinOp > beta, ptr_param< LinOp > x) const |
| Ic< solver::LowerTrs<>, int32 > * | apply (ptr_param< const LinOp > alpha, ptr_param< const LinOp > b, ptr_param< const LinOp > beta, ptr_param< LinOp > x) |
Public Member Functions inherited from gko::EnableAbstractPolymorphicObject< Ic< solver::LowerTrs<>, int32 >, LinOp > | |
| std::unique_ptr< Ic< solver::LowerTrs<>, int32 > > | create_default (std::shared_ptr< const Executor > exec) const |
| std::unique_ptr< Ic< solver::LowerTrs<>, int32 > > | create_default () const |
| std::unique_ptr< Ic< solver::LowerTrs<>, int32 > > | clone (std::shared_ptr< const Executor > exec) const |
| std::unique_ptr< Ic< solver::LowerTrs<>, int32 > > | clone () const |
| Ic< solver::LowerTrs<>, int32 > * | copy_from (const PolymorphicObject *other) |
| std::enable_if_t< std::is_base_of< PolymorphicObject, std::decay_t< Derived > >::value, Ic< solver::LowerTrs<>, int32 > > * | copy_from (std::unique_ptr< Derived > &&other) |
| std::enable_if_t< std::is_base_of< PolymorphicObject, std::decay_t< Derived > >::value, Ic< solver::LowerTrs<>, int32 > > * | copy_from (const std::unique_ptr< Derived > &other) |
| Ic< solver::LowerTrs<>, int32 > * | copy_from (const std::shared_ptr< const PolymorphicObject > &other) |
| Ic< solver::LowerTrs<>, int32 > * | move_from (ptr_param< PolymorphicObject > other) |
| Ic< solver::LowerTrs<>, int32 > * | clear () |
Public Member Functions inherited from gko::LinOp | |
| LinOp * | apply (ptr_param< const LinOp > b, ptr_param< LinOp > x) |
| Applies a linear operator to a vector (or a sequence of vectors). | |
| const LinOp * | apply (ptr_param< const LinOp > b, ptr_param< LinOp > x) const |
| LinOp * | apply (ptr_param< const LinOp > alpha, ptr_param< const LinOp > b, ptr_param< const LinOp > beta, ptr_param< LinOp > x) |
| Performs the operation x = alpha * op(b) + beta * x. | |
| const LinOp * | apply (ptr_param< const LinOp > alpha, ptr_param< const LinOp > b, ptr_param< const LinOp > beta, ptr_param< LinOp > x) const |
| const dim< 2 > & | get_size () const noexcept |
| Returns the size of the operator. | |
| virtual bool | apply_uses_initial_guess () const |
| Returns true if the linear operator uses the data given in x as an initial guess. | |
| LinOp & | operator= (const LinOp &)=default |
| Copy-assigns a LinOp. | |
| LinOp & | operator= (LinOp &&other) |
| Move-assigns a LinOp. | |
| LinOp (const LinOp &)=default | |
| Copy-constructs a LinOp. | |
| LinOp (LinOp &&other) | |
| Move-constructs a LinOp. | |
Public Member Functions inherited from gko::EnableAbstractPolymorphicObject< LinOp > | |
| std::unique_ptr< LinOp > | create_default (std::shared_ptr< const Executor > exec) const |
| std::unique_ptr< LinOp > | create_default () const |
| std::unique_ptr< LinOp > | clone (std::shared_ptr< const Executor > exec) const |
| std::unique_ptr< LinOp > | clone () const |
| LinOp * | copy_from (const PolymorphicObject *other) |
| std::enable_if_t< std::is_base_of< PolymorphicObject, std::decay_t< Derived > >::value, LinOp > * | copy_from (std::unique_ptr< Derived > &&other) |
| std::enable_if_t< std::is_base_of< PolymorphicObject, std::decay_t< Derived > >::value, LinOp > * | copy_from (const std::unique_ptr< Derived > &other) |
| LinOp * | copy_from (const std::shared_ptr< const PolymorphicObject > &other) |
| LinOp * | move_from (ptr_param< PolymorphicObject > other) |
| LinOp * | clear () |
Public Member Functions inherited from gko::PolymorphicObject | |
| PolymorphicObject & | operator= (const PolymorphicObject &) |
| std::unique_ptr< PolymorphicObject > | create_default (std::shared_ptr< const Executor > exec) const |
| Creates a new "default" object of the same dynamic type as this object. | |
| std::unique_ptr< PolymorphicObject > | create_default () const |
| Creates a new "default" object of the same dynamic type as this object. | |
| std::unique_ptr< PolymorphicObject > | clone (std::shared_ptr< const Executor > exec) const |
| Creates a clone of the object. | |
| std::unique_ptr< PolymorphicObject > | clone () const |
| Creates a clone of the object. | |
| PolymorphicObject * | copy_from (const PolymorphicObject *other) |
| Copies another object into this object. | |
| template<typename Derived, typename Deleter> | |
| std::enable_if_t< std::is_base_of< PolymorphicObject, std::decay_t< Derived > >::value, PolymorphicObject > * | copy_from (std::unique_ptr< Derived, Deleter > &&other) |
| Moves another object into this object. | |
| template<typename Derived, typename Deleter> | |
| std::enable_if_t< std::is_base_of< PolymorphicObject, std::decay_t< Derived > >::value, PolymorphicObject > * | copy_from (const std::unique_ptr< Derived, Deleter > &other) |
| Copies another object into this object. | |
| PolymorphicObject * | copy_from (const std::shared_ptr< const PolymorphicObject > &other) |
| Copies another object into this object. | |
| PolymorphicObject * | move_from (ptr_param< PolymorphicObject > other) |
| Moves another object into this object. | |
| PolymorphicObject * | clear () |
| Transforms the object into its default state. | |
| std::shared_ptr< const Executor > | get_executor () const noexcept |
| Returns the Executor of the object. | |
Public Member Functions inherited from gko::log::EnableLogging< PolymorphicObject > | |
| void | add_logger (std::shared_ptr< const Logger > logger) override |
| Adds a new logger to the list of subscribed loggers. | |
| void | remove_logger (const Logger *logger) override |
| Removes a logger from the list of subscribed loggers. | |
| void | remove_logger (ptr_param< const Logger > logger) |
| const std::vector< std::shared_ptr< const Logger > > & | get_loggers () const override |
| Returns the vector containing all loggers registered at this object. | |
| void | clear_loggers () override |
| Remove all loggers registered at this object. | |
Public Member Functions inherited from gko::log::Loggable | |
| void | remove_logger (ptr_param< const Logger > logger) |
Public Member Functions inherited from gko::EnablePolymorphicAssignment< Ic< solver::LowerTrs<>, int32 > > | |
| void | convert_to (result_type *result) const override |
| void | move_to (result_type *result) override |
Public Member Functions inherited from gko::ConvertibleTo< Ic< solver::LowerTrs<>, int32 > > | |
| void | convert_to (ptr_param< result_type > result) const |
| void | move_to (ptr_param< result_type > result) |
Static Public Member Functions | |
| static auto | build () -> decltype(Factory::create()) |
| static parameters_type | parse (const config::pnode &config, const config::registry &context, const config::type_descriptor &td_for_child=config::make_type_descriptor< value_type, index_type >()) |
| Create the parameters from the property_tree. | |
Friends | |
| class | EnableLinOp< Ic > |
| class | EnablePolymorphicObject< Ic, LinOp > |
The Incomplete Cholesky (IC) preconditioner solves the equation 
It allows to set both the solver for L defaulting to solver::LowerTrs, which is a direct triangular solvers. The solver for L^H is the conjugate-transposed solver for L, ensuring that the preconditioner is symmetric and positive-definite. For this L solver, a factory can be provided (using with_l_solver) to have more control over their behavior. In particular, it is possible to use an iterative method for solving the triangular systems. The default parameters for an iterative triangluar solver are:
An object of this class can be created with a matrix or a gko::Composition containing two matrices. If created with a matrix, it is factorized before creating the solver. If a gko::Composition (containing two matrices) is used, the first operand will be taken as the L matrix, the second will be considered the L^H matrix, which helps to avoid the otherwise necessary transposition of L inside the solver. ParIc can be directly used, since it orders the factors in the correct way.


| LSolverType | type of the solver used for the L matrix. Defaults to solver::LowerTrs |
| IndexType | type of the indices when ParIc is used to generate the L and L^H factors. Irrelevant otherwise. |
|
inline |
Copy-constructs an IC preconditioner.
Inherits the executor, shallow-copies the solvers and parameters.
|
inline |
Move-constructs an IC preconditioner.
Inherits the executor, moves the solvers and parameters. The moved-from object is empty (0x0 with nullptr solvers and default parameters)
|
inlineoverridevirtual |
Returns a LinOp representing the conjugate transpose of the Transposable object.
Implements gko::Transposable.
Referenced by conj_transpose().
|
inline |
Returns the solver which is used for the provided L matrix.
Referenced by conj_transpose(), and transpose().
|
inline |
Returns the solver which is used for the L^H matrix.
Referenced by conj_transpose(), and transpose().
|
inline |
Copy-assigns an IC preconditioner.
Preserves the executor, shallow-copies the solvers and parameters. Creates a clone of the solvers if they are on the wrong executor.
|
inline |
Move-assigns an IC preconditioner.
Preserves the executor, moves the solvers and parameters. Creates a clone of the solvers if they are on the wrong executor. The moved-from object is empty (0x0 with nullptr solvers and default parameters)
|
inlinestatic |
Create the parameters from the property_tree.
Because this is directly tied to the specific type, the value/index type settings within config are ignored and type_descriptor is only used for children configs.
| config | the property tree for setting |
| context | the registry |
| td_for_child | the type descriptor for children configs. The default uses the value/index type of this class. |
|
inlineoverridevirtual |
Returns a LinOp representing the transpose of the Transposable object.
Implements gko::Transposable.
Referenced by transpose().