/IMPL/SOLVER

Engine Keyword Selects linear solver.

Format

/IMPL/SOLVER/N

Iprec It_max Itol Tol

Definition

Field Contents SI Unit Example
N Linear solver method number (solve Ax=b).
= 0
Set to 2.
= 1
Iterative solver. Preconditioned Conjugate Gradient (PCG).
= 2 (Default)
Direct solver MUMPS.
  
Iprec Precondition methods.
= 0
Set to 5.
= 1
No preconditioner.
= 2
Diagonal Jacobi.
= 5
Factored approximate inverse.
  
It_max Maximum iteration number used for stop criteria.
= 0 or > NDOF
Set to NDOF (system dimension).
  
Itol Stop criteria for Preconditioned iterative solver flag.
= 0
Set to 3.
= 1
Relative Residual of original matrix (residual r = A x − b , ‖ r ‖ < T o l * ‖ b ‖ MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbwvMCKf MBHbqefqvATv2CG4uz3bIuV1wyUbqedmvETj2BSbqefm0B1jxALjhi ov2DaebbnrfifHhDYfgasaacH8akY=xipgYlh9vqqj=hEeei0xXdbb a9frFf0=yqFf0dbba91qpepeI8k8fiI+fsY=rqaqpepae9pg0Firpe pesP0xe9Fve9Fve9qapdbaGaaiGadiWaamaaceGaaqaacaqbaaGcba GaamOCaiabg2da9iaadgeacaWG4bGaeyOeI0IaamOyaiaacYcadaqb diqaaiaadkhaaiaawMa7caGLkWoacqGH8aapcaWGubGaam4BaiaadY gacaGGQaWaauWaceaacaWGIbaacaGLjWUaayPcSdaaaa@4CBA@ ).
= 2
Relative Residual of preconditioned matrix ( ‖ r ‖ < T o l * ‖ b ' ‖ MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbwvMCKf MBHbqefqvATv2CG4uz3bIuV1wyUbqedmvETj2BSbqefm0B1jxALjhi ov2DaebbnrfifHhDYfgasaacH8akY=xipgYlh9vqqj=hEeei0xXdbb a9frFf0=yqFf0dbba91qpepeI8k8fiI+fsY=rqaqpepae9pg0Firpe pesP0xe9Fve9Fve9qapdbaGaaiGadiWaamaaceGaaqaacaqbaaGcba WaauWaceaacaWGYbaacaGLjWUaayPcSdGaeyipaWJaamivaiaad+ga caWGSbGaaiOkamaafmGabaGaamOyaiaacEcaaiaawMa7caGLkWoaaa a@4721@ ).
= 3
Relative Residual of preconditioned matrix ( ‖ r ‖ < T o l * ‖ b ' ‖ * ‖ A ' ‖ * ‖ x ‖ MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbwvMCKf MBHbqefqvATv2CG4uz3bIuV1wyUbqedmvETj2BSbqefm0B1jxALjhi ov2DaebbnrfifHhDYfgasaacH8akY=xipgYlh9vqqj=hEeei0xXdbb a9frFf0=yqFf0dbba91qpepeI8k8fiI+fsY=rqaqpepae9pg0Firpe pesP0xe9Fve9Fve9qapdbaGaaiGadiWaamaaceGaaqaacaqbaaGcba WaauWaceaacaWGYbaacaGLjWUaayPcSdGaeyipaWJaamivaiaad+ga caWGSbGaaiOkamaafmGabaGaamOyaiaacEcaaiaawMa7caGLkWoaca GGQaWaauWaceaacaWGbbGaai4jaaGaayzcSlaawQa7aiaacQcadaqb diqaaiaadIhaaiaawMa7caGLkWoaaaa@513D@ ).
  
Tol Input tolerance for stop criteria.
= 0.0
Set to 1.0e-5, if Itol =1 or 2 set to machine simple precision, if Itol =3.
  

Comments

  1. When this keyword is not defined, all default values will be used.
  2. Linear solvers are also used in nonlinear iterations. When /IMPL/NONLIN/N is used, the linear solver parameters, rather than default values can be defined in this keyword.