/* nag_sparse_herm_chol_sol (f11jqc) Example Program. * * Copyright 2011, Numerical Algorithms Group. * * Mark 23, 2011. */ #include #include #include #include int main(void) { /* Scalars */ Integer exit_status = 0; double dscale, dtol, rnorm, tol; Integer i, itn, la, lfill, maxitn, n, nnz, nnzc, npivm; /* Arrays */ char nag_enum_arg[40]; Complex *a = 0, *b = 0, *x = 0; Integer *icol = 0, *ipiv = 0, *irow = 0, *istr = 0; /* NAG types */ Nag_SparseSym_Method method; Nag_SparseSym_Piv pstrat; Nag_SparseSym_Fact mic; NagError fail; INIT_FAIL(fail); printf("nag_sparse_herm_chol_sol (f11jqc) Example Program Results\n\n"); /* Skip heading in data file*/ scanf("%*[^\n]"); /* Read algorithmic parameters*/ scanf("%ld%*[^\n]", &n); scanf("%ld%*[^\n]", &nnz); /* Allocate memory */ la = 3 * nnz; if ( !(a = NAG_ALLOC(la, Complex)) || !(b = NAG_ALLOC(n, Complex)) || !(x = NAG_ALLOC(n, Complex)) || !(icol = NAG_ALLOC(la, Integer)) || !(ipiv = NAG_ALLOC(n, Integer)) || !(irow = NAG_ALLOC(la, Integer)) || !(istr = NAG_ALLOC(n + 1, Integer)) ) { printf("Allocation failure\n"); exit_status = -1; goto END; } 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("%"NAG_IFMT "%lf%*[^\n]", &lfill, &dtol); scanf("%s%*[^\n]", nag_enum_arg); mic = (Nag_SparseSym_Fact) nag_enum_name_to_value(nag_enum_arg); scanf("%lf%*[^\n]", &dscale); scanf("%s%*[^\n]", nag_enum_arg); pstrat = (Nag_SparseNsym_Piv) nag_enum_name_to_value(nag_enum_arg); scanf("%lf%ld%*[^\n]", &tol, &maxitn); /* Read the matrix a */ for (i = 0; i < nnz; i++) scanf(" ( %lf , %lf ) %ld%ld%*[^\n] ", &a[i].re, &a[i].im, &irow[i], &icol[i]); /* Read rhs vector b and initial approximate solution x */ for (i = 0; i < n; i++) scanf(" ( %lf , %lf ) ", &b[i].re, &b[i].im); scanf("%*[^\n]"); for (i = 0; i < n; i++) scanf(" ( %lf , %lf ) ", &x[i].re, &x[i].im); /* Calculate incomplete Cholesky factorization of complex sparse Hermitian * matrix using nag_sparse_herm_chol_fac (f11jnc). */ nag_sparse_herm_chol_fac(n, nnz, a, la, irow, icol, lfill, dtol, mic, dscale, pstrat, ipiv, istr, &nnzc, &npivm, &fail); if (fail.code != NE_NOERROR) { printf("Error from nag_sparse_herm_chol_fac (f11jnc).\n%s\n", fail.message); exit_status = 1; goto END; } /* Solve Linear System. */ /* nag_sparse_herm_chol_sol (f11jqc). * Solution of complex sparse Hermitian linear system, conjugate * gradient/Lanczos method, preconditioner computed by f11jnc */ nag_sparse_herm_chol_sol(method, n, nnz, a, la, irow, icol, ipiv, istr, b, tol, maxitn, x, &rnorm, &itn, &fail); if (fail.code != NE_NOERROR) { printf("Error from nag_sparse_herm_chol_sol.(f11jqc)\n%s\n", fail.message); exit_status = 2; goto END; } printf("Converged in %10ld iterations \n",itn); printf("Final residual norm = %10.3e\n\n", rnorm); printf(" Converged Solution\n"); /* Output x*/ for (i = 0; i < n; i++) printf(" (%11.4e, %11.4e)\n", x[i].re, x[i].im); END: if (a) NAG_FREE(a); if (b) NAG_FREE(b); if (x) NAG_FREE(x); if (icol) NAG_FREE(icol); if (ipiv) NAG_FREE(ipiv); if (irow) NAG_FREE(irow); if (istr) NAG_FREE(istr); return exit_status; }