nag_sparse_herm_precon_ssor_solve (f11jrc) solves a system of equations
involving the preconditioning matrix
corresponding to symmetric successive-over-relaxation (SSOR) (see
Young (1971)) on a linear system
, where
is a sparse complex Hermitian matrix stored in symmetric coordinate storage (SCS) format (see
Section 2.1.2 in the f11 Chapter Introduction).
- NE_ALLOC_FAIL
-
Dynamic memory allocation failed.
See
Section 2.3.1.2 in How to Use the NAG Library and its Documentation for further information.
- NE_BAD_PARAM
-
On entry, argument had an illegal value.
- NE_INT
-
On entry, .
Constraint: .
On entry, .
Constraint: .
- NE_INT_2
-
On entry, and .
Constraint: .
- NE_INTERNAL_ERROR
-
An internal error has occurred in this function. Check the function call and any array sizes. If the call is correct then please contact
NAG for assistance.
See
Section 2.7.6 in How to Use the NAG Library and its Documentation for further information.
- NE_INVALID_SCS
-
On entry, , , .
Constraint: .
On entry, , and .
Constraint: .
- NE_NO_LICENCE
-
Your licence key may have expired or may not have been installed correctly.
See
Section 2.7.5 in How to Use the NAG Library and its Documentation for further information.
- NE_NOT_STRICTLY_INCREASING
-
On entry, is out of order: .
On entry, the location (
) is a duplicate:
. Consider calling
nag_sparse_herm_sort (f11zpc) to reorder and sum or remove duplicates.
- NE_REAL
-
On entry, .
Constraint: .
- NE_ZERO_DIAG_ELEM
-
The matrix has no diagonal entry in row .
The computed solution
is the exact solution of a perturbed system of equations
, where
is a modest linear function of
, and
is the
machine precision.
The time taken for a call to
nag_sparse_herm_precon_ssor_solve (f11jrc) is proportional to
nnz.