Optimist  0.0.0
A C++ library for optimization
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Optimist::RootFinder::Greenstadt< Real, N > Class Template Reference

Class container for the Greenstadt's method. More...

#include <Greenstadt.hh>

Inherits Optimist::RootFinder::QuasiNewton< Real, N, Greenstadt< Real, N > >.

Public Types

using Method = enum class Method : Integer {ONE = 1, TWO = 2}
 
using Vector = typename QuasiNewton<Real, N, Greenstadt<Real, N>>::Vector
 
using Matrix = typename QuasiNewton<Real, N, Greenstadt<Real, N>>::Matrix
 
using FunctionWrapper = typename QuasiNewton<Real, N, Greenstadt<Real, N>>::FunctionWrapper
 
using JacobianWrapper = typename QuasiNewton<Real, N, Greenstadt<Real, N>>::JacobianWrapper
 
- Public Types inherited from Optimist::RootFinder::QuasiNewton< Real, N, Greenstadt< Real, N > >
using Method
 
using Vector
 
using Matrix
 
using FunctionWrapper
 
using JacobianWrapper
 
- Public Types inherited from Optimist::RootFinder::RootFinder< Real, N, Greenstadt< Real, N > >
using Vector
 
using Matrix
 
using Tensor
 
using FunctionWrapper
 
using JacobianWrapper
 
using HessianWrapper
 

Public Member Functions

 Greenstadt ()
 
std::string name_impl () const
 
Method method () const
 
void method (Method t_method)
 
void enable_one_method ()
 
void enable_two_method ()
 
void set_method (Method t_method)
 
void update_impl (Vector const &, Vector const &, Matrix const &jacobian_old, Vector const &delta_x_new, Vector const &delta_function_new, Vector const &function_new, Matrix &jacobian_new)
 
- Public Member Functions inherited from Optimist::RootFinder::QuasiNewton< Real, N, Greenstadt< Real, N > >
 QuasiNewton ()
 
std::string name_impl () const
 
bool solve_impl (FunctionWrapper function, JacobianWrapper jacobian, Vector const &x_ini, Vector &x_sol)
 
void update (Vector const &delta_x_old, Vector const &delta_function_old, Matrix const &jacobian_old, Vector const &delta_x_new, Vector const &delta_function_new, Vector const &function_new, Matrix &jacobian_new)
 
- Public Member Functions inherited from Optimist::RootFinder::RootFinder< Real, N, Greenstadt< Real, N > >
 RootFinder ()
 
std::string name () const
 
Integer jacobian_evaluations () const
 
Integer max_jacobian_evaluations () const
 
void max_jacobian_evaluations (Integer t_jacobian_evaluations)
 
Integer hessian_evaluations () const
 
Integer max_hessian_evaluations () const
 
void max_hessian_evaluations (Integer t_hessian_evaluations)
 
bool solve (FunctionWrapper function, Vector const &x_ini, Vector &x_sol)
 
bool solve (FunctionWrapper function, JacobianWrapper jacobian, Vector const &x_ini, Vector &x_sol)
 
bool solve (FunctionWrapper function, JacobianWrapper jacobian, HessianWrapper hessian, Vector const &x_ini, Vector &x_sol)
 
- Public Member Functions inherited from Optimist::Solver< Real, N, N, Greenstadt< Real, N > >
 Solver ()
 
 Solver (FunctionWrapper function, const InputType &x_ini, InputType &x_sol)
 
 Solver (FunctionWrapper function, FirstDerivativeWrapper first_derivative, const InputType &x_ini, InputType &x_sol)
 
 Solver (FunctionWrapper function, FirstDerivativeWrapper first_derivative, SecondDerivativeWrapper second_derivative, const InputType &x_ini, InputType &x_sol)
 
const InputTypelower_bound () const
 
void lower_bound (const InputType &t_lower_bound)
 
const InputTypeupper_bound () const
 
void upper_bound (const InputType &t_upper_bound)
 
void bounds (const InputType &t_lower_bound, const InputType &t_upper_bound)
 
constexpr Integer input_dimension () const
 
constexpr Integer output_dimension () const
 
Integer function_evaluations () const
 
void max_function_evaluations (Integer t_max_function_evaluations)
 
Integer max_function_evaluations () const
 
Integer iterations () const
 
Integer max_iterations () const
 
void max_iterations (Integer t_max_iterations)
 
Real alpha () const
 
void alpha (Real t_alpha)
 
Integer relaxations () const
 
Integer max_relaxations () const
 
void max_relaxations (Integer t_max_relaxations)
 
Real tolerance () const
 
void tolerance (Real t_tolerance)
 
void verbose_mode (bool t_verbose)
 
bool verbose_mode () const
 
void enable_verbose_mode ()
 
void disable_verbose_mode ()
 
void damped_mode (bool t_damped)
 
bool damped_mode () const
 
void enable_damped_mode ()
 
void disable_damped_mode ()
 
std::string task () const
 
void task (std::string t_task)
 
bool converged () const
 
const TraceTypetrace () const
 
std::ostream & ostream () const
 
void ostream (std::ostream &t_ostream)
 
bool solve (FunctionWrapper function, const InputType &x_ini, InputType &x_sol)
 
bool solve (FunctionWrapper function, FirstDerivativeWrapper first_derivative, const InputType &x_ini, InputType &x_sol)
 
bool solve (FunctionWrapper function, FirstDerivativeWrapper first_derivative, SecondDerivativeWrapper second_derivative, const InputType &x_ini, InputType &x_sol)
 
bool rootfind (Function< Real, FunInDim, FunOutDim, DerivedFunction > const &function, const InputType &x_ini, InputType &x_sol)
 
bool optimize (Function< Real, FunInDim, FunOutDim, DerivedFunction > const &function, const InputType &x_ini, InputType &x_sol)
 
std::string name () const
 

Static Public Attributes

static constexpr bool requires_function {true}
 
static constexpr bool requires_first_derivative {true}
 
static constexpr bool requires_second_derivative {false}
 
- Static Public Attributes inherited from Optimist::RootFinder::QuasiNewton< Real, N, Greenstadt< Real, N > >
static constexpr bool requires_function
 
static constexpr bool requires_first_derivative
 
static constexpr bool requires_second_derivative
 
- Static Public Attributes inherited from Optimist::RootFinder::RootFinder< Real, N, Greenstadt< Real, N > >
static constexpr bool is_rootfinder
 
static constexpr bool is_optimizer
 
static constexpr bool requires_function
 
static constexpr bool requires_first_derivative
 
static constexpr bool requires_second_derivative
 

Private Attributes

Method m_method {Method::ONE}
 

Additional Inherited Members

- Public Attributes inherited from Optimist::RootFinder::RootFinder< Real, N, Greenstadt< Real, N > >
friend Solver< Real, N, N, RootFinder< Real, N, DerivedSolver > >
 
- Protected Types inherited from Optimist::Solver< Real, N, N, Greenstadt< Real, N > >
using InputType
 
using OutputType
 
using TraceType
 
using FirstDerivativeType
 
using SecondDerivativeType
 
using FunctionWrapper
 
using FirstDerivativeWrapper
 
using SecondDerivativeWrapper
 
- Protected Member Functions inherited from Optimist::RootFinder::RootFinder< Real, N, Greenstadt< Real, N > >
void evaluate_jacobian (JacobianWrapper jacobian, const Vector &x, Matrix &out)
 
void evaluate_hessian (HessianWrapper hessian, const Vector &x, Matrix &out)
 
- Protected Member Functions inherited from Optimist::Solver< Real, N, N, Greenstadt< Real, N > >
Integer first_derivative_evaluations () const
 
Integer max_first_derivative_evaluations () const
 
void max_first_derivative_evaluations (Integer first_derivative_evaluations)
 
Integer second_derivative_evaluations () const
 
Integer max_second_derivative_evaluations () const
 
void max_second_derivative_evaluations (Integer second_derivative_evaluations)
 
bool solve (Function< Real, FunInDim, FunOutDim, DerivedFunction > const &function, const InputType &x_ini, InputType &x_sol, bool is_optimization)
 
void reset ()
 
void evaluate_function (FunctionWrapper function, const InputType &x, OutputType &out)
 
void evaluate_first_derivative (FirstDerivativeWrapper function, const InputType &x, FirstDerivativeType &out)
 
void evaluate_second_derivative (SecondDerivativeWrapper function, const InputType &x, SecondDerivativeType &out)
 
void store_trace (const InputType &x)
 
bool damp (FunctionWrapper function, InputType const &x_old, InputType const &function_old, InputType const &step_old, InputType &x_new, InputType &function_new, InputType &step_new)
 
void header ()
 
void bottom ()
 
void info (Real residuals, std::string const &notes="-")
 
- Protected Attributes inherited from Optimist::Solver< Real, N, N, Greenstadt< Real, N > >
InputType m_lower_bound
 
InputType m_upper_bound
 
Integer m_function_evaluations
 
Integer m_first_derivative_evaluations
 
Integer m_second_derivative_evaluations
 
Integer m_max_function_evaluations
 
Integer m_max_first_derivative_evaluations
 
Integer m_max_second_derivative_evaluations
 
Integer m_iterations
 
Integer m_max_iterations
 
Real m_alpha
 
Integer m_relaxations
 
Integer m_max_relaxations
 
Real m_tolerance
 
bool m_verbose
 
bool m_damped
 
std::ostream * m_ostream
 
std::string m_task
 
bool m_converged
 
TraceType m_trace
 

Detailed Description

template<typename Real, Integer N>
class Optimist::RootFinder::Greenstadt< Real, N >

Greenstadt's method

Similarly to the Broyden's methods, Greenstadt's methods are quasi-Newton methods that approximates the Jacobian matrix \(\mathbf{Jf}_{\mathbf{x}}\) an update rule. The generic Greenstadt's method is defined as

\[ \mathbf{H}_k(\mathbf{x}_k) \mathbf{h}_k = -\mathbf{f}(\mathbf{x}_k) \text{,} \]

where \(\mathbf{H}_k\) is the (inverse) Jacobian approximation at the \(k\)-th iteration.

Based on the update rule, Greenstadt's method is classified into two methods: trivially method 1 and method 2. The update of the Jacobian approximation is performed as

\[ \mathbf{H}_{k+1}^{-1} = \mathbf{H}_k^{-1} - \displaystyle\frac{\mathbf{H}_k^{-1} \Delta\mathbf{f}_k - \Delta\mathbf{x}_k}{\mathbf{g} \Delta\mathbf{f}_k} \mathbf{g} \text{,} \]

where \(\Delta\mathbf{x}_k = \mathbf{x}_k - \mathbf{x}_{k-1}\), and \(\Delta\mathbf{f}_k = \mathbf{f}(\mathbf{x}_k) - \mathbf{f}(\mathbf{x}_{k-1})\). The quantity \(\mathbf{g}\) is \(\mathbf{g} = \mathbf{f}_k^\top\) for method 1 and \(\mathbf{g} = \mathbf{H}_{k\top}^{-1} \mathbf{H}_k^{-1} \Delta\mathbf{f}_k^{\top}\) for method 2. The choice of the method is based on the convergence history, switching between the methods to adapt to the problem's behavior.

For more details on the Greenstadt's methods refer to the reference: Spedicato E., Greenstadt J. On some classes of variationally derived Quasi-Newton methods for systems of nonlinear algebraic equations, Numerische Mathematik, 29 (1978), pp. 363-380.

Template Parameters
RealScalar number type.
NDimension of the root-finding problem.

Member Typedef Documentation

◆ FunctionWrapper

template<typename Real, Integer N>
using Optimist::RootFinder::Greenstadt< Real, N >::FunctionWrapper = typename QuasiNewton<Real, N, Greenstadt<Real, N>>::FunctionWrapper

◆ JacobianWrapper

template<typename Real, Integer N>
using Optimist::RootFinder::Greenstadt< Real, N >::JacobianWrapper = typename QuasiNewton<Real, N, Greenstadt<Real, N>>::JacobianWrapper

◆ Matrix

template<typename Real, Integer N>
using Optimist::RootFinder::Greenstadt< Real, N >::Matrix = typename QuasiNewton<Real, N, Greenstadt<Real, N>>::Matrix

◆ Method

template<typename Real, Integer N>
using Optimist::RootFinder::Greenstadt< Real, N >::Method = enum class Method : Integer {ONE = 1, TWO = 2}

Greenstadt solver type.

◆ Vector

template<typename Real, Integer N>
using Optimist::RootFinder::Greenstadt< Real, N >::Vector = typename QuasiNewton<Real, N, Greenstadt<Real, N>>::Vector

Constructor & Destructor Documentation

◆ Greenstadt()

template<typename Real, Integer N>
Optimist::RootFinder::Greenstadt< Real, N >::Greenstadt ( )
inline

Class constructor for the Greenstadt solver.

Member Function Documentation

◆ enable_one_method()

template<typename Real, Integer N>
void Optimist::RootFinder::Greenstadt< Real, N >::enable_one_method ( )
inline

Enable the Greenstadt1 solver method.

◆ enable_two_method()

template<typename Real, Integer N>
void Optimist::RootFinder::Greenstadt< Real, N >::enable_two_method ( )
inline

Enable the Greenstadt2 solver method.

◆ method() [1/2]

template<typename Real, Integer N>
Method Optimist::RootFinder::Greenstadt< Real, N >::method ( ) const
inline

Get the enumeration type of the Greenstadt solver method.

Returns
The Greenstadt solver enumeration type.

◆ method() [2/2]

template<typename Real, Integer N>
void Optimist::RootFinder::Greenstadt< Real, N >::method ( Method t_method)
inline

Set the enumeration type of the Greenstadt solver method.

Parameters
[in]t_methodThe Greenstadt solver method enumeration type.

◆ name_impl()

template<typename Real, Integer N>
std::string Optimist::RootFinder::Greenstadt< Real, N >::name_impl ( ) const
inline

Get the Greenstadt solver name.

Returns
The Greenstadt solver name.

◆ set_method()

template<typename Real, Integer N>
void Optimist::RootFinder::Greenstadt< Real, N >::set_method ( Method t_method)
inline

Set the Greenstadt solver method.

Parameters
[in]t_methodThe Greenstadt solver method enumeration type.

◆ update_impl()

template<typename Real, Integer N>
void Optimist::RootFinder::Greenstadt< Real, N >::update_impl ( Vector const & ,
Vector const & ,
Matrix const & jacobian_old,
Vector const & delta_x_new,
Vector const & delta_function_new,
Vector const & function_new,
Matrix & jacobian_new )
inline

Jacobian approximation update rule for the Greenstadt's method.

Parameters
[in]delta_x_oldOld difference between points.
[in]delta_function_oldOld difference between function values.
[in]jacobian_oldOld jacobian approximation.
[in]delta_x_newNew difference between points.
[in]delta_function_newNew difference between function values.
[in]function_newNew function value.
[out]jacobian_newNew jacobian approximation.

Member Data Documentation

◆ m_method

template<typename Real, Integer N>
Method Optimist::RootFinder::Greenstadt< Real, N >::m_method {Method::ONE}
private

Greenstadt solver type.

◆ requires_first_derivative

template<typename Real, Integer N>
bool Optimist::RootFinder::Greenstadt< Real, N >::requires_first_derivative {true}
staticconstexpr

◆ requires_function

template<typename Real, Integer N>
bool Optimist::RootFinder::Greenstadt< Real, N >::requires_function {true}
staticconstexpr

◆ requires_second_derivative

template<typename Real, Integer N>
bool Optimist::RootFinder::Greenstadt< Real, N >::requires_second_derivative {false}
staticconstexpr

Basic constants.


The documentation for this class was generated from the following file: