/* nag_dtgsyl (f08yhc) Example Program. * * Copyright 2011 Numerical Algorithms Group. * * Mark 23, 2011. */ #include #include #include #include #include int main(void) { /* Scalars */ double dif, scale; Integer i, ijob, j, m, n, pda, pdb, pdc, pdd, pde, pdf; Integer exit_status = 0; /* Arrays */ double *a = 0, *b = 0, *c = 0, *d = 0, *e = 0, *f = 0; char nag_enum_arg[40]; /* Nag Types */ NagError fail; Nag_OrderType order; Nag_TransType trans; /* K(I,J) maps matrix element (I,J) to array storage element k */ #ifdef NAG_COLUMN_MAJOR #define K(I, J, PD) (J-1)*PD + I - 1 order = Nag_ColMajor; #else #define K(I, J, PD) (I-1)*PD + J - 1 order = Nag_RowMajor; #endif INIT_FAIL(fail); printf("nag_dtgsyl (f08yhc) Example Program Results\n\n"); /* Skip heading in data file */ scanf("%*[^\n]"); scanf("%ld%ld%*[^\n]", &m, &n); scanf("%ld%*[^\n]", &ijob); if (m < 0 || n < 0 || ijob < 0 || ijob > 4) { printf("Invalid m, n or ijob\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 */ trans = ( Nag_TransType) nag_enum_name_to_value(nag_enum_arg); pda = m; pdb = n; pdd = m; pde = n; #ifdef NAG_COLUMN_MAJOR pdc = m; pdf = m; #else pdc = n; pdf = n; #endif /* Allocate memory */ if (!(a = NAG_ALLOC(m*m, double)) || !(b = NAG_ALLOC(n*n, double)) || !(c = NAG_ALLOC(m*n, double)) || !(d = NAG_ALLOC(m*m, double)) || !(e = NAG_ALLOC(n*n, double)) || !(f = NAG_ALLOC(m*n, double))) { printf("Allocation failure\n"); exit_status = -1; goto END; } /* Read A, B, D, E, C and F from data file */ for (i = 1; i <= m; ++i) for (j = 1; j <= m; ++j) scanf("%lf", &a[K(i, j, pda)]); scanf("%*[^\n]"); for (i = 1; i <= n; ++i) for (j = 1; j <= n; ++j) scanf("%lf", &b[K(i, j, pdb)]); scanf("%*[^\n]"); for (i = 1; i <= m; ++i) for (j = 1; j <= m; ++j) scanf("%lf", &d[K(i, j, pdd)]); scanf("%*[^\n]"); for (i = 1; i <= n; ++i) for (j = 1; j <= n; ++j) scanf("%lf", &e[K(i, j, pde)]); scanf("%*[^\n]"); for (i = 1; i <= m; ++i) for (j = 1; j <= n; ++j) scanf("%lf", &c[K(i, j, pdc)]); scanf("%*[^\n]"); for (i = 1; i <= m; ++i) for (j = 1; j <= n; ++j) scanf("%lf", &f[K(i, j, pdf)]); scanf("%*[^\n]"); /* Solve the Sylvester equations: * A*R - L*B = scale*C * D*R - L*E = scale*F * for R and L using nag_dtgsyl (f08yhc). */ nag_dtgsyl(order, trans, ijob, m, n, a, pda, b, pdb, c, pdc, d, pdd, e, pde, f, pdf, &scale, &dif, &fail); if (fail.code != NE_NOERROR) { printf("Error from nag_dtgsyl (f08yhc).\n%s\n", fail.message); exit_status = 1; goto END; } /* Print the solution matrices R and L */ fflush(stdout); nag_gen_real_mat_print(order, Nag_GeneralMatrix, Nag_NonUnitDiag, m, n, c, pdc, "Solution matrix R", 0, &fail); if (fail.code != NE_NOERROR) { printf("Error from nag_gen_real_mat_print (x04cac).\n%s\n", fail.message); exit_status = 1; goto END; } printf("\n"); fflush(stdout); nag_gen_real_mat_print(order, Nag_GeneralMatrix, Nag_NonUnitDiag, m, n, f, pdf, "Solution matrix L", 0, &fail); if (fail.code != NE_NOERROR) { printf("Error from nag_gen_real_mat_print (x04cac).\n%s\n", fail.message); exit_status = 1; goto END; } printf("\nscale = %11.2e\n", scale); if (ijob>0 && scale>0.0) { printf("\ndif = %11.2e\n\n", dif); printf("This estimate of Dif((A,D),(B,E)) was computed based on the "); if (ijob==1 || ijob==3) { printf("Frobenius norm.\n"); } else { printf("one norm.\n"); } } END: if (a) NAG_FREE(a); if (b) NAG_FREE(b); if (c) NAG_FREE(c); if (d) NAG_FREE(d); if (e) NAG_FREE(e); if (f) NAG_FREE(f); return exit_status; }