NAME

BSpar_solve - General solver of a system of equations preconditioned by one of several preconditioners and using one of several possible methods. The rhs can be a block of vectors.

INPUT PARAMETERS

A: - a sparse matrix
fact_A: - the incomplete factored version of A, if any
comm_A: - the communication structure for A
rhs: - the contiguous block of vectors forming the rhs
residual: - the final computed residual

OUTPUT PARAMETERS

x: - the contiguous block of vectors containing the solution (can contain an initial guess if BSctx_set_guess() is set.

NOW SPECIFIED IN PROCINFO CONTEXT

pre_option: - the preconditioner to use: PRE_ICC: incomplete Cholesky factorization PRE_ILU: incomplete LU factorization PRE_SSOR: Successive over relaxation PRE_BJACOBI: Block Jacobi
err_tol: - the tolerance to which to solve the problem stop if the estimated 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
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

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_solve. For more information on the preconditioners, see the manual or BSctx_set_pre().

SYNOPSIS

int BSpar_solve(BSpar_mat *A, BSpar_mat *fact_A, BScomm *comm_A,
 FLOAT *rhs, FLOAT *x, FLOAT *residual, BSprocinfo *procinfo)

LOCATION

BlockSolve95/src/BSpar_solve.c