BSpar_gmres(3) BlockSolve95 BSpar_gmres(3)NAMEBSpar_gmres - Solve a nonsymmetric system of equations using gmres pre‐
conditioned by one of several preconditioners. The rhs can be a block
of vectors.
INPUT PARAMETERS
BS - the number of vectors in the RHS
A - a sparse matrix
fact_A - the incomplete factored version of A, if any
comm_A - the communication structure for A
in_rhs - the contiguous block of vectors forming the rhs
pre_option
- the preconditioner to use PRE_ICC: incomplete Cholesky factor‐
ization PRE_ILU: incomplete LU factorization PRE_SSOR: Succes‐
sive over relaxation PRE_BJACOBI: Block Jacobi
err_tol
- the tolerance to which to solve the problem stop if the esti‐
mated norm of the residual divided by the norm of the rhs is
less than err_tol
max_iter
- the maximum number of iterations to take
residual
- the final computed residual
guess - if TRUE, then initialize out_x to 0, otherwise the program
assumes that out_x contains an initial guess
procinfo
- the usual processor stuff
OUTPUT PARAMETERS
out_x - the contiguous block of vectors containing the solution
RETURNS
The number of iterations or a negative number indicating the number of
iterations prior to finding that the matrix (or preconditioner) is not
positive definite.
NOTES
The preconditioners must be computed prior to calling BSpar_isolve.
For more information on the preconditioners, see the manual.
SYNOPSIS
int BSpar_gmres(int BS, BSpar_mat *A, BSpar_mat *fact_A, BScomm *comm_A,
FLOAT *in_rhs, FLOAT *out_x, int pre_option, int restart, FLOAT err_tol,
int max_iter, FLOAT *residual, int guess, BSprocinfo *procinfo)
LOCATION
BlockSolve95/src/BSpar_gmres.c
12/25/1995 BSpar_gmres(3)
