Description
Base class for Chrono solvers based on Eigen iterative linear solvers.
Iterative linear solvers.
Cannot handle VI and complementarity problems, so they cannot be used with NSC formulations.
All iterative solvers are implemented in a matrix-free context and rely on the system descriptor for the required SPMV operations. See ChSystemDescriptor for more information about the problem formulation and the data structures passed to the solver.
The default value for the maximum number of iterations is twice the matrix size.
The threshold value specified through SetTolerance is used by the stopping criteria as an upper bound to the relative residual error: |Ax - b|/|b|. Default: machine precision.
By default, these solvers use a diagonal preconditioner and no warm start. Recall that the warm start option should be used only in conjunction with the Euler implicit linearized integrator.
#include <ChIterativeSolverLS.h>
Public Member Functions | |
| virtual bool | Setup (ChSystemDescriptor &sysd) override |
| Perform the solver setup operations. More... | |
| virtual double | Solve (ChSystemDescriptor &sysd) override |
| Performs the solution of the problem. More... | |
 Public Member Functions inherited from chrono::ChIterativeSolver | |
| virtual 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. | |
| virtual int | GetIterations () const =0 |
| Return the number of iterations performed during the last solve. | |
| virtual double | GetError () const =0 |
| Return the tolerance error reached during the last solve. | |
| Public Member Functions inherited from chrono::ChSolver | |
| virtual Type | GetType () const |
| Return type of the solver. | |
| virtual ChDirectSolverLS * | AsDirect () |
| Downcast to ChDirectSolver. | |
| void | SetVerbose (bool mv) |
| Set verbose output from solver. | |
| void | EnableWrite (bool val, const std::string &frame, const std::string &out_dir=".") |
| Enable/disable debug output of matrix, RHS, and solution vector. | |
| virtual void | ArchiveOut (ChArchiveOut &archive_out) |
| Method to allow serialization of transient data to archives. | |
| virtual void | ArchiveIn (ChArchiveIn &archive_in) |
| Method to allow de-serialization of transient data from archives. | |
Protected Member Functions | |
| virtual bool | IsIterative () const override |
| Return true if iterative solver. | |
| virtual bool | IsDirect () const override |
| Return true if direct solver. | |
| virtual ChIterativeSolver * | AsIterative () override |
| Downcast to ChIterativeSolver. | |
| virtual bool | SolveRequiresMatrix () const override final |
| Indicate whether or not the Solve() phase requires an up-to-date problem matrix. | |
| virtual bool | SetupProblem ()=0 |
| Initialize the solver with the current sparse matrix and return true if successful. | |
| virtual bool | SolveProblem ()=0 |
| Solve the linear system using the current factorization and right-hand side vector. More... | |
| Protected Member Functions inherited from chrono::ChIterativeSolver | |
| ChIterativeSolver (int max_iterations, double tolerance, bool use_precond, bool warm_start) | |
| void | WriteMatrices (ChSystemDescriptor &sysd, bool one_indexed=true) |
| double | CheckSolution (ChSystemDescriptor &sysd, const ChVectorDynamic<> &x) |
Protected Attributes | |
| ChMatrixSPMV * | m_spmv |
| matrix-like wrapper for SPMV operations | |
| ChVectorDynamic< double > | m_sol |
| solution vector | |
| ChVectorDynamic< double > | m_rhs |
| right-hand side vector | |
| ChVectorDynamic< double > | m_invdiag |
| inverse diagonal entries (for preconditioning) | |
| ChVectorDynamic< double > | m_initguess |
| initial guess (for warm start) | |
| 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 | |
| Protected Attributes inherited from chrono::ChSolver | |
| bool | verbose |
| bool | write_matrix |
| std::string | output_dir |
| std::string | frame_id |
Additional Inherited Members | |
| Public Types inherited from chrono::ChSolver | |
| enum | Type { Type::PSOR, Type::PSSOR, Type::PJACOBI, Type::PMINRES, Type::BARZILAIBORWEIN, Type::APGD, Type::ADMM, Type::SPARSE_LU, Type::SPARSE_QR, Type::PARDISO_MKL, Type::MUMPS, Type::GMRES, Type::MINRES, Type::BICGSTAB, CUSTOM } |
| Available types of solvers. More... | |
| Static Public Member Functions inherited from chrono::ChSolver | |
| static std::string | GetTypeAsString (Type type) |
| Return the solver type as a string. | |
Member Function Documentation
◆ Setup()
|
overridevirtual |
Perform the solver setup operations.
Here, sysd is the system description with constraints and variables. Returns true if successful and false otherwise.
Reimplemented from chrono::ChSolver.
◆ Solve()
|
overridevirtual |
Performs the solution of the problem.
Return the maximum constraint violation after termination.
Implements chrono::ChSolver.
◆ SolveProblem()
|
protectedpure virtual |
Solve the linear system using the current factorization and right-hand side vector.
Load the solution vector (already of appropriate size) and return true if succesful.
The documentation for this class was generated from the following files:
- /builds/uwsbel/chrono/src/chrono/solver/ChIterativeSolverLS.h
- /builds/uwsbel/chrono/src/chrono/solver/ChIterativeSolverLS.cpp
