petsc-3.12.5 2020-03-29
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MatCreateLMVMBrdn

Creates a limited-memory "good" Broyden-type approximation matrix used for a Jacobian. L-Brdn is not guaranteed to be symmetric or positive-definite.

Synopsis

#include "petscksp.h" 
PetscErrorCode MatCreateLMVMBrdn(MPI_Comm comm, PetscInt n, PetscInt N, Mat *B)
The provided local and global sizes must match the solution and function vectors used with MatLMVMUpdate() and MatSolve(). The resulting L-Brdn matrix will have storage vectors allocated with VecCreateSeq() in serial and VecCreateMPI() in parallel. To use the L-Brdn matrix with other vector types, the matrix must be created using MatCreate() and MatSetType(), followed by MatLMVMAllocate(). This ensures that the internal storage and work vectors are duplicated from the correct type of vector.

Collective

Input Parameters

comm - MPI communicator, set to PETSC_COMM_SELF
n - number of local rows for storage vectors
N - global size of the storage vectors

Output Parameter

B -the matrix

It is recommended that one use the MatCreate(), MatSetType() and/or MatSetFromOptions() paradigm instead of this routine directly.

Options Database Keys

-mat_lmvm_num_vecs -maximum number of correction vectors (i.e.: updates) stored

See Also

MatCreate(), MATLMVM, MATLMVMBRDN, MatCreateLMVMDFP(), MatCreateLMVMSR1(),
MatCreateLMVMBFGS(), MatCreateLMVMBadBrdn(), MatCreateLMVMSymBrdn()

Level

intermediate

Location

src/ksp/ksp/utils/lmvm/brdn/brdn.c
Index of all KSP routines
Table of Contents for all manual pages
Index of all manual pages