IncompleteLUPreconditioner<T> Constructor

Definition

Namespace: Numerics.NET.LinearAlgebra.IterativeSolvers.Preconditioners
Assembly: Numerics.NET (in Numerics.NET.dll) Version: 10.9.0

Overload List

IncompleteLUPreconditioner<T>(SparseMatrix<T>)Constructs an ILU(0) preconditioner with pivot protection, optional regularization and ordering.
IncompleteLUPreconditioner<T>(SparseMatrix<T>, T, T, Boolean, Permutation)Constructs an ILU(0) preconditioner with pivot protection, optional regularization and ordering.

IncompleteLUPreconditioner<T>(SparseMatrix<T>)

Constructs an ILU(0) preconditioner with pivot protection, optional regularization and ordering.
C# 
public IncompleteLUPreconditioner(
	SparseMatrix<T> matrix
)

Parameters

matrix  SparseMatrix<T>
A non-null square sparse matrix.

Remarks

Uses natural ordering, no shift or equilibration, and a relative pivot tolerance of 100 times the scalar machine epsilon.

Exceptions

ArgumentNullExceptionmatrix is null.
DimensionMismatchExceptionThe matrix is not square or the ordering has the wrong length.
ArgumentOutOfRangeExceptionA tuning value is outside its valid range.
ArgumentExceptionThe ordering is not a permutation or coefficients/factors are nonfinite.
MatrixSingularExceptionA diagonal is missing without a requested shift, or a pivot is zero or too small.

IncompleteLUPreconditioner<T>(SparseMatrix<T>, T, T, Boolean, Permutation)

Constructs an ILU(0) preconditioner with pivot protection, optional regularization and ordering.
C# 
public IncompleteLUPreconditioner(
	SparseMatrix<T> matrix,
	T relativePivotTolerance,
	T relativeDiagonalShift,
	bool equilibrateRows = false,
	Permutation? ordering = null
)

Parameters

matrix  SparseMatrix<T>
A non-null square sparse matrix.
relativePivotTolerance  T
A finite real value in [0, 1). Pivots whose magnitude divided by the maximum magnitude in their shifted row is at most this value are rejected.
relativeDiagonalShift  T
A finite nonnegative real value. The diagonal is shifted by this value times the original row maximum magnitude, or unit scale for an empty row. Only the preconditioner is shifted.
equilibrateRows  Boolean  (Optional)
Whether to divide each shifted row by its maximum entry magnitude before factorization.
ordering  Permutation  (Optional)
An optional permutation mapping factor coordinates to original coordinates. It applies to both rows and columns and is copied during construction. Null uses natural ordering.

Exceptions

ArgumentNullExceptionmatrix is null.
DimensionMismatchExceptionThe matrix is not square or the ordering has the wrong length.
ArgumentOutOfRangeExceptionA tuning value is outside its valid range.
ArgumentExceptionThe ordering is not a permutation or coefficients/factors are nonfinite.
MatrixSingularExceptionA diagonal is missing without a requested shift, or a pivot is zero or too small.

See Also