/* nag_sparse_nsym_jacobi (f11dkc) Example Program. * * Copyright 2011, Numerical Algorithms Group. * * Mark 23, 2011. */ #include #include #include int main(void) { /* Scalars */ Integer exit_status = 0; double anorm, sigmax, stplhs, stprhs, tol; Integer i, irevcm, iterm, itn, lwork, lwreq, m, maxitn, monit, n, niter, nnz; /* Arrays */ char nag_enum_arg[100]; double *a = 0, *b = 0, *diag = 0, *wgt = 0, *work = 0, *x = 0; Integer *icol = 0, *irow = 0; /* NAG types */ Nag_InitializeA init; Nag_SparseNsym_Method method; Nag_SparseNsym_PrecType precon; Nag_NormType norm; Nag_SparseNsym_Weight weight; NagError fail, fail1; INIT_FAIL(fail); INIT_FAIL(fail1); printf("nag_sparse_nsym_jacobi (f11dkc) Example Program Results \n"); /* Skip heading in data file */ scanf("%*[^\n]"); scanf("%ld%*[^\n]", &n); scanf("%ld%*[^\n]", &nnz); lwork = 200; if ( !(a = NAG_ALLOC((nnz), double)) || !(b = NAG_ALLOC((n), double)) || !(diag = NAG_ALLOC((n), double)) || !(wgt = NAG_ALLOC((n), double)) || !(work = NAG_ALLOC((lwork), double)) || !(x = NAG_ALLOC((n), double)) || !(icol = NAG_ALLOC((nnz), Integer)) || !(irow = NAG_ALLOC((nnz), Integer)) ) { printf("Allocation failure\n"); exit_status = -1; goto END; } /* Read or initialize the parameters for the iterative solver */ scanf("%s%*[^\n]", nag_enum_arg); /* nag_enum_name_to_value(x04nac). * Converts NAG enum member name to value */ method = (Nag_SparseNsym_Method) nag_enum_name_to_value(nag_enum_arg); scanf("%s%*[^\n]", nag_enum_arg); precon = (Nag_SparseNsym_PrecType) nag_enum_name_to_value(nag_enum_arg); scanf("%s%*[^\n]", nag_enum_arg); norm = (Nag_NormType) nag_enum_name_to_value(nag_enum_arg); scanf("%s%*[^\n]", nag_enum_arg); weight = (Nag_SparseNsym_Weight) nag_enum_name_to_value(nag_enum_arg); scanf("%ld%*[^\n]", &iterm); scanf("%ld%lf%ld%*[^\n]", &m, &tol, &maxitn); scanf("%ld%*[^\n]", &monit); /* Read the parameters for the preconditioner */ scanf("%ld%*[^\n]", &niter); anorm = 0.0; sigmax = 0.0; /* Read the non-zero elements of the matrix A */ for (i = 0; i <= nnz - 1; i++) scanf("%lf%ld%ld%*[^\n]", &a[i], &irow[i], &icol[i]); /* Read right-hand side vector b and initial approximate solution */ for (i = 0; i <= n - 1; i++) scanf("%lf", &b[i]); scanf("%*[^\n]"); for (i = 0; i <= n - 1; i++) scanf("%lf", &x[i]); /* nag_sparse_nsym_basic_setup (f11bdc) * Real sparse nonsymmetric linear systems, setup routine */ nag_sparse_nsym_basic_setup(method, precon, norm, weight, iterm, n, m, tol, maxitn, anorm, sigmax, monit, &lwreq, work, lwork, &fail); if (fail.code != NE_NOERROR) { printf("Error from nag_sparse_nsym_basic_setup (f11bdc).\n%s\n", fail.message); exit_status = 1; goto END; } /* call solver repeatedly to solve the equations * Note that the arrays b and x are overwritten * On final exit, x will contain the solution and b the residual vector */ irevcm = 0; lwreq = lwork; init = Nag_InitializeI; while (irevcm != 4) { /* nag_sparse_nsym_basic_solver (f11bec) * Real sparse nonsymmetric linear systems, solver routine * preconditioned RGMRES, CGS, Bi-CGSTAB or TFQMR method */ nag_sparse_nsym_basic_solver(&irevcm, x, b, wgt, work, lwreq, &fail); switch (irevcm) { case -1: /* nag_sparse_nsym_matvec (f11xac) * Real sparse nonsymmetric matrix vector multiply */ nag_sparse_nsym_matvec(Nag_Trans, n, nnz, a, irow, icol, Nag_SparseNsym_NoCheck, x, b, &fail1); break; case 1: nag_sparse_nsym_matvec(Nag_NoTrans, n, nnz, a, irow, icol, Nag_SparseNsym_NoCheck, x, b, &fail1); break; case 2: /* nag_sparse_nsym_jacobi (f11dkc) * Real sparse nonsymmetric linear systems, line Jacobi preconditioner */ nag_sparse_nsym_jacobi(Nag_SparseNsym_StoreCS, Nag_NoTrans, init, niter, n, nnz, a, irow, icol, Nag_SparseNsym_Check, x, b, diag, &fail1); init = Nag_InputA; break; case 3: /* nag_sparse_nsym_basic_diagnostic (f11bfc) * Real sparse nonsymmetric linear systems, diagnostic for f11bec */ nag_sparse_nsym_basic_diagnostic(&itn, &stplhs, &stprhs, &anorm, &sigmax, work, lwreq, &fail1); printf("%ld %f \n", itn, stplhs); } if (fail1.code != NE_NOERROR) irevcm = 6; } if (fail.code != NE_NOERROR) { printf("Error from nag_sparse_nsym_basic_solver (f11bec)\n%s\n", fail.message); exit_status = 2; goto END; } /* Obtain information about the computation*/ nag_sparse_nsym_basic_diagnostic(&itn, &stplhs, &stprhs, &anorm, &sigmax, work, lwreq, &fail); /* Print the output data*/ printf("\nFinal Results\n"); printf("Number of iterations for convergence: %5ld \n", itn); printf("Residual norm: %14.4e\n", stplhs); printf("Right-hand side of termination criterion: %14.4e\n", stprhs); printf("1-norm of matrix A: %14.4e\n\n", anorm); /* Output x*/ printf("%16s%16s\n","Solution","Residuals"); for (i = 0; i < n; i++) printf("%16.4f%16.4e\n", x[i], b[i]); END: if (a) NAG_FREE(a); if (b) NAG_FREE(b); if (diag) NAG_FREE(diag); if (wgt) NAG_FREE(wgt); if (work) NAG_FREE(work); if (x) NAG_FREE(x); if (icol) NAG_FREE(icol); if (irow) NAG_FREE(irow); return exit_status; }