chrono::ChSolverBB Class Reference

Description

An iterative solver based on modified Krylov iteration of spectral projected gradients with Barzilai-Borwein.

The Barzilai-Borwein solver can use diagonal preconditioning (enabled by default).

See ChSystemDescriptor for more information about the problem formulation and the data structures passed to the solver.

#include <ChSolverBB.h>

Inheritance diagram for chrono::ChSolverBB:
Collaboration diagram for chrono::ChSolverBB:

Public Member Functions

virtual Type GetType () const override
 Return type of the solver.
 
virtual double Solve (ChSystemDescriptor &sysd) override
 Performs the solution of the problem. More...
 
void SetNarmijo (int mf)
 Number of max tolerated steps in non-monotone Armijo line search; usually good values are in 1..10 range.
 
double GetNarmijo ()
 
void SetMaxArmijoBacktrace (int mm)
 
int GetMaxArmijoBacktrace ()
 
virtual double GetError () const override
 Return the tolerance error reached during the last solve. More...
 
virtual void ArchiveOUT (ChArchiveOut &marchive) override
 Method to allow serialization of transient data to archives.
 
virtual void ArchiveIN (ChArchiveIn &marchive) override
 Method to allow de serialization of transient data from archives.
 
- Public Member Functions inherited from chrono::ChIterativeSolverVI
void SetOmega (double mval)
 Set the overrelaxation factor (default: 1.0). More...
 
void SetSharpnessLambda (double mval)
 Set the sharpness factor (default: 1.0). More...
 
void SetRecordViolation (bool mval)
 Enable/disable recording of the constraint violation history. More...
 
double GetOmega () const
 Return the current value of the overrelaxation factor.
 
double GetSharpnessLambda () const
 Return the current value of the sharpness factor.
 
virtual int GetIterations () const override
 Return the number of iterations performed during the last solve.
 
const std::vector< double > & GetViolationHistory () const
 Access the vector of constraint violation history. More...
 
const std::vector< double > & GetDeltalambdaHistory () const
 Access the vector with history of maximum change in Lagrange multipliers Note that collection of constraint violations must be enabled through SetRecordViolation.
 
- Public Member Functions inherited from chrono::ChSolver
virtual bool Setup (ChSystemDescriptor &sysd)
 This function does the setup operations for the solver. More...
 
void SetVerbose (bool mv)
 Set verbose output from solver.
 
- Public Member Functions inherited from chrono::ChIterativeSolver
void SetMaxIterations (int max_iterations)
 Set the maximum number of iterations.
 
void SetTolerance (double tolerance)
 Set the tolerance threshold used by the stopping criteria.
 
void EnableDiagonalPreconditioner (bool val)
 Enable/disable use of a simple diagonal preconditioner (default: true). More...
 
void EnableWarmStart (bool val)
 Enable/disable warm starting by providing an initial guess (default: false). More...
 
int GetMaxIterations () const
 Get the current maximum number of iterations.
 
double GetTolerance () const
 Get the current tolerance value.
 

Additional Inherited Members

- Public Types inherited from chrono::ChSolver
enum  Type {
  Type::PSOR = 0, Type::PSSOR, Type::PJACOBI, Type::PMINRES,
  Type::BARZILAIBORWEIN, Type::APGD, Type::PARDISO, Type::MUMPS,
  Type::GMRES, Type::MINRES, Type::BICGSTAB, CUSTOM
}
 Available types of solvers. More...
 
- Protected Member Functions inherited from chrono::ChIterativeSolverVI
void AtIterationEnd (double mmaxviolation, double mdeltalambda, unsigned int iternum)
 This method MUST be called by all iterative methods INSIDE their iteration loops (at the end). More...
 
virtual bool SolveRequiresMatrix () const override
 Indicate whether ot not the Solve() phase requires an up-to-date problem matrix. More...
 
- Protected Member Functions inherited from chrono::ChIterativeSolver
 ChIterativeSolver (int max_iterations, double tolerance, bool use_precond, bool warm_start)
 
void SaveMatrix (ChSystemDescriptor &sysd)
 
double CheckSolution (ChSystemDescriptor &sysd, const ChVectorDynamic<> &x)
 
- Protected Attributes inherited from chrono::ChIterativeSolverVI
int m_iterations
 total number of iterations performed by the solver
 
double m_omega
 over-relaxation factor
 
double m_shlambda
 sharpness factor
 
bool record_violation_history
 
std::vector< double > violation_history
 
std::vector< double > dlambda_history
 
- Protected Attributes inherited from chrono::ChSolver
bool verbose
 
- Protected Attributes inherited from chrono::ChIterativeSolver
bool m_use_precond
 use diagonal preconditioning?
 
bool m_warm_start
 use initial guesss?
 
int m_max_iterations
 maximum number of iterations
 
double m_tolerance
 tolerance threshold in stopping criteria
 

Member Function Documentation

◆ GetError()

virtual double chrono::ChSolverBB::GetError ( ) const
inlineoverridevirtual

Return the tolerance error reached during the last solve.

For the Barzilai-Borwein solver, this is the norm of the projected gradient.

Implements chrono::ChIterativeSolver.

◆ Solve()

double chrono::ChSolverBB::Solve ( ChSystemDescriptor sysd)
overridevirtual

Performs the solution of the problem.

Returns
the maximum constraint violation after termination.
Parameters
sysdsystem description with constraints and variables

Implements chrono::ChSolver.


The documentation for this class was generated from the following files:
  • C:/Users/udarn/Repositories/chrono/src/chrono/solver/ChSolverBB.h
  • C:/Users/udarn/Repositories/chrono/src/chrono/solver/ChSolverBB.cpp