mundy::CGStrategy< ResidualPolicy, Config, Precond > Class Template Reference

The CG strategy: initialize/iterate/done/result over (Problem, State), preconditioned by Precond. More...

#include <linear_system.hpp>

Public Types
using	value_type = typename Config::value_type
using	residual_policy_t = ResidualPolicy
using	config_t = Config
using	preconditioner_t = Precond
using	result_t = CGResult<value_type>

Public Member Functions
	CGStrategy (residual_policy_t resid, config_t cfg={})
	CGStrategy (residual_policy_t resid, config_t cfg, Precond &&precond)
const auto &	precond () const
template<class Problem, class State>
void	initialize (const Problem &prob, State &state) const
template<class Problem, class State>
bool	iterate (const Problem &prob, State &state) const
template<class State>
bool	done (const State &state) const
template<class State>
result_t	result (const State &state) const

Detailed Description

template<class ResidualPolicy, class Config, class Precond = NoPreconditioner>
class mundy::CGStrategy< ResidualPolicy, Config, Precond >

alpha/beta are fixed by the conjugate-direction recurrence, so there is no step policy – only how the residual is measured (ResidualPolicy, a VectorResidualPolicy) and the preconditioner P (a Preconditioner) are pluggable. The residual measured is that of A x = b, with or without P. CG starts from alpha x for the caller's guess x, alpha = x^T b / x^T A x, the multiple of x nearest the solution in the A-norm, wherever x^T A x > 0.

Member Typedef Documentation

value_type

template<class ResidualPolicy, class Config, class Precond = NoPreconditioner>

using mundy::CGStrategy< ResidualPolicy, Config, Precond >::value_type = typename Config::value_type

residual_policy_t

template<class ResidualPolicy, class Config, class Precond = NoPreconditioner>

using mundy::CGStrategy< ResidualPolicy, Config, Precond >::residual_policy_t = ResidualPolicy

config_t

template<class ResidualPolicy, class Config, class Precond = NoPreconditioner>

using mundy::CGStrategy< ResidualPolicy, Config, Precond >::config_t = Config

preconditioner_t

template<class ResidualPolicy, class Config, class Precond = NoPreconditioner>

using mundy::CGStrategy< ResidualPolicy, Config, Precond >::preconditioner_t = Precond

result_t

template<class ResidualPolicy, class Config, class Precond = NoPreconditioner>

using mundy::CGStrategy< ResidualPolicy, Config, Precond >::result_t = CGResult<value_type>

Constructor & Destructor Documentation

CGStrategy() [1/2]

template<class ResidualPolicy, class Config, class Precond = NoPreconditioner>

mundy::CGStrategy< ResidualPolicy, Config, Precond >::CGStrategy ( residual_policy_t resid, config_t cfg = {} )

inline

CGStrategy() [2/2]

template<class ResidualPolicy, class Config, class Precond = NoPreconditioner>

mundy::CGStrategy< ResidualPolicy, Config, Precond >::CGStrategy ( residual_policy_t resid, config_t cfg, Precond && precond )

inline

Member Function Documentation

precond()

template<class ResidualPolicy, class Config, class Precond = NoPreconditioner>

const auto & mundy::CGStrategy< ResidualPolicy, Config, Precond >::precond ( ) const

inline

initialize()

template<class ResidualPolicy, class Config, class Precond = NoPreconditioner>

template<class Problem, class State>

void mundy::CGStrategy< ResidualPolicy, Config, Precond >::initialize ( const Problem & prob, State & state ) const

inline

iterate()

template<class ResidualPolicy, class Config, class Precond = NoPreconditioner>

template<class Problem, class State>

bool mundy::CGStrategy< ResidualPolicy, Config, Precond >::iterate ( const Problem & prob, State & state ) const

inline

done()

template<class ResidualPolicy, class Config, class Precond = NoPreconditioner>

template<class State>

bool mundy::CGStrategy< ResidualPolicy, Config, Precond >::done ( const State & state ) const

inline

result()

template<class ResidualPolicy, class Config, class Precond = NoPreconditioner>

template<class State>

result_t mundy::CGStrategy< ResidualPolicy, Config, Precond >::result ( const State & state ) const

inline