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BSpar_solve(3)                   BlockSolve95                   BSpar_solve(3)

## 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 1/10/1996 BSpar_solve(3)

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