Preconditioners

AMGPrecon(sparsematrix::AbstractSparseMatrix; 
             blocksize=1, 
             param=nothing)

Create algebraic multigrid preconditioner with ldiv! and \ methods solving the preconditioning system.

Parameters:

• sparsematrix: SparseArrays.AbstractSparseMatrixCSC or SparseMatricesCSR.SparseMatrixCSR.
• blocksize: If blocksize >1, group unknowns into blocks of given size and cast the matrix internally to a sparse matrix of blocksize x blocksize static matrices. Block sizes 1...8 are instantiated.
• param: Any object (e.g. Tuple, Dict or JSON string) which can be turned into a JSON string by JSON3.write. If params is an emtpy string or nothing a default value is used.

AMGPrecon(sparsematrix::AbstractSparseMatrix; blocksize::Int=1, param=nothing, verbose::Bool=false, coarsening::Union{AbstractCoarsening, NamedTuple}=SmoothedAggregationCoarsening(), relax::Union{AbstractRelaxation, NamedTuple}=SPAI0Relaxation()) Create algebraic multigrid preconditioner with ldiv! and \ methods solving the preconditioning system.

Parameters:

• sparsematrix: SparseArrays.AbstractSparseMatrixCSC or SparseMatricesCSR.SparseMatrixCSR.

• sparsematrix: SparseArrays.AbstractSparseMatrixCSC or SparseMatricesCSR.SparseMatrixCSR.

• blocksize: If blocksize >1, group unknowns into blocks of given size and cast the matrix internally to a sparse matrix of blocksize x blocksize static matrices. Block sizes 1...8 are instantiated.

• verbose: if true, print generated JSON string passed to amgcl.

• param: Ignored if nothing (default). Otherwise, any object (e.g. Tuple, Dict or JSON string) which can be turned into a JSON string by JSON3.write.

• coarsening: A coarsening strategy

• relax: A relaxation method

RLXPrecon(sparsematrix::AbstractSparseMatrix; 
             blocksize=1, 
             param=nothing)

Create single level relaxation preconditioner with ldiv! and \ methods solving the preconditioning system.

Parameters:

• sparsematrix: SparseArrays.AbstractSparseMatrixCSC or SparseMatricesCSR.SparseMatrixCSR.
• blocksize: If blocksize >1, group unknowns into blocks of given size and cast the matrix internally to a sparse matrix of blocksize x blocksize static matrices. Block sizes 1...8 are instantiated.
• param: Any object (e.g. Tuple, Dict or JSON string) which can be turned into a JSON string by JSON3.write. If params is an emtpy string or nothing a default value is used.