NewtonCgPreconditioner Enumeration

Specifies how Newton conjugate-gradient steps are preconditioned.

Definition

Namespace: Numerics.NET.Optimization
Assembly: Numerics.NET (in Numerics.NET.dll) Version: 10.9.0
C#
public enum NewtonCgPreconditioner

Remarks

Preconditioning makes the inner linear solve easier without changing the objective.

Members

Automatic0Uses incomplete Cholesky for sparse entries, a supplied diagonal, or limited-memory history.
None1Uses no preconditioner.
Diagonal2Uses the magnitude of a supplied or recovered Hessian diagonal.
LimitedMemoryBfgs3Uses inverse BFGS updates from accepted gradients.
IncompleteCholesky4Uses incomplete Cholesky on the sparse Hessian pattern.
ModifiedIncompleteCholesky5Uses modified incomplete Cholesky restricted to the current free variables.

See Also