PCLUSetUseInPlace

Tells the system to do an in-place factorization. For dense matrices, this enables the solution of much larger problems. For sparse matrices the factorization cannot be done truly in-place so this does not save memory during the factorization, but after the matrix is factored, the original unfactored matrix is freed, thus recovering that space.

Synopsis

int PCLUSetUseInPlace(PC pc)
Collective on PC

Input Parameters

pc -the preconditioner context

Options Database Key

-pc_lu_in_place -Activates in-place factorization

Notes

PCLUSetUseInplace() can only be used with the KSP method KSPPREONLY or when a different matrix is provided for the multiply and the preconditioner in a call to SLESSetOperators(). This is because the Krylov space methods require an application of the matrix multiplication, which is not possible here because the matrix has been factored in-place, replacing the original matrix.

Keywords

PC, set, factorization, direct, inplace, in-place, LU

See Also

PCILUSetUseInPlace()

Level:intermediate
Location:src/sles/pc/impls/lu/lu.c
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