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Ginkgo Generated from branch based on main. Ginkgo version 1.10.0
A numerical linear algebra library targeting many-core architectures
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Rcm (Reverse Cuthill-McKee) is a reordering algorithm minimizing the bandwidth of a matrix. More...
#include <ginkgo/core/reorder/rcm.hpp>
Classes | |
struct | parameters_type |
Public Types | |
using | index_type = IndexType |
using | permutation_type = matrix::Permutation<index_type> |
Public Types inherited from gko::EnablePolymorphicAssignment< Rcm< int32 > > | |
using | result_type |
Public Types inherited from gko::ConvertibleTo< Rcm< int32 > > | |
using | result_type |
Public Member Functions | |
const parameters_type & | get_parameters () |
Returns the parameters used to construct the factory. | |
std::unique_ptr< permutation_type > | generate (std::shared_ptr< const LinOp > system_matrix) const |
Creates a new product from the given components. | |
Public Member Functions inherited from gko::EnableAbstractPolymorphicObject< Rcm< int32 >, LinOpFactory > | |
std::unique_ptr< Rcm< int32 > > | create_default (std::shared_ptr< const Executor > exec) const |
std::unique_ptr< Rcm< int32 > > | clone (std::shared_ptr< const Executor > exec) const |
Rcm< int32 > * | copy_from (const PolymorphicObject *other) |
Rcm< int32 > * | move_from (ptr_param< PolymorphicObject > other) |
Rcm< int32 > * | clear () |
Public Member Functions inherited from gko::LinOpFactory | |
std::unique_ptr< LinOp > | generate (std::shared_ptr< const LinOp > input) const |
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. | |
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< Rcm< int32 > > | |
void | convert_to (result_type *result) const override |
void | move_to (result_type *result) override |
Static Public Member Functions | |
static parameters_type | build () |
Creates a new parameter_type to set up the factory. |
Friends | |
class | EnablePolymorphicObject< Rcm< IndexType >, LinOpFactory > |
class | enable_parameters_type< parameters_type, Rcm< IndexType > > |
Rcm (Reverse Cuthill-McKee) is a reordering algorithm minimizing the bandwidth of a matrix.
Such a reordering typically also significantly reduces fill-in, though usually not as effective as more complex algorithms, specifically AMD and nested dissection schemes. The advantage of this algorithm is its low runtime.
The class is a LinOpFactory generating a Permutation matrix out of a Csr system matrix, to be used with Csr::permute(...).
There are two "starting strategies" currently available: minimum degree and pseudo-peripheral. These strategies control how a starting vertex for a connected component is chosen, which is then renumbered as first vertex in the component, starting the algorithm from there. In general, the bandwidths obtained by choosing a pseudo-peripheral vertex are slightly smaller than those obtained from choosing a vertex of minimum degree. On the other hand, this strategy is much more expensive, relatively. The algorithm for finding a pseudo-peripheral vertex as described in "Computer Solution of Sparse Linear Systems" (George, Liu, Ng, Oak Ridge National Laboratory, 1994) is implemented here.
IndexType | Type of the indices of all matrices used in this class |
std::unique_ptr< permutation_type > gko::experimental::reorder::Rcm< IndexType >::generate | ( | std::shared_ptr< const LinOp > | system_matrix | ) | const |
Creates a new product from the given components.
The method will create an ComponentsType object from the arguments of this method, and pass it to the generate_impl() function which will create a new AbstractProductType.
Args | types of arguments passed to the constructor of ComponentsType |
args | arguments passed to the constructor of ComponentsType |
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inline |
Returns the parameters used to construct the factory.