spm.c

 *
 * @brief Check backward and forward errors
 *
 * Check the backward error, and the forward error if x0 is provided.
 *
 *******************************************************************************
 *
 * @param[in] nrhs
 *          Defines the number of right hand side that must be generated.
 *
 * @param[in] spm
 *          The sparse matrix uses to generate the right hand side, and the
 *          solution of the full problem.
 *
 * @param[in,out] x0
 *          If x0 != NULL, the forward error is computed.
 *          On exit, x0 stores (x0-x)
 *
 * @param[in] ldx0
 *          Defines the leading dimension of x0 when multiple right hand sides
 *          are available. ldx0 >= spm->n.
 *
 * @param[in,out] b
 *          b is a matrix of size at least ldb * nrhs.
 *          On exit, b stores Ax-b.
 *
 * @param[in] ldb
 *          Defines the leading dimension of b when multiple right hand sides
 *          are available. ldb >= spm->n.
 *
 * @param[in] x
 *          Contains the solution computed by the solver.
 *
 * @param[in] ldx
 *          Defines the leading dimension of x when multiple right hand sides
 *          are available. ldx >= spm->n.
 *
 *******************************************************************************
 *
 * @return
 *      \retval PASTIX_SUCCESS if the b vector has been computed succesfully,
 *      \retval PASTIX_ERR_BADPARAMETER otherwise.
 *
 *******************************************************************************/
int
spmCheckAxb( int nrhs,
             const pastix_spm_t  *spm,
                   void *x0, int ldx0,
                   void *b,  int ldb,
             const void *x,  int ldx )
{
    static int (*ptrfunc[4])(int, const pastix_spm_t *,
                             void *, int, void *, int, const void *, int) =
        {
            s_spmCheckAxb, d_spmCheckAxb, c_spmCheckAxb, z_spmCheckAxb
        };

    int id = spm->flttype - PastixFloat;
    if ( (id < 0) || (id > 3) ) {
        return PASTIX_ERR_BADPARAMETER;
    }
    else {
        return ptrfunc[id](nrhs, spm, x0, ldx0, b, ldb, x, ldx );
    }
}