/* nag_zhseqr (f08psc) Example Program. * * Copyright 2001 Numerical Algorithms Group. * * Mark 7, 2001. */ #include #include #include #include #include int main(void) { /* Scalars */ Integer i, j, n, pdh, pdz, w_len; Integer exit_status=0; NagError fail; Nag_OrderType order; /* Arrays */ Complex *h=0, *w=0, *z=0; #ifdef NAG_COLUMN_MAJOR #define H(I,J) h[(J-1)*pdh + I - 1] order = Nag_ColMajor; #else #define H(I,J) h[(I-1)*pdh + J - 1] order = Nag_RowMajor; #endif INIT_FAIL(fail); Vprintf("nag_zhseqr (f08psc) Example Program Results\n\n"); /* Skip heading in data file */ Vscanf("%*[^\n] "); Vscanf("%ld%*[^\n] ", &n); #ifdef NAG_COLUMN_MAJOR pdh = n; pdz = n; #else pdh = n; pdz = n; #endif w_len = n; /* Allocate memory */ if ( !(h = NAG_ALLOC(n * n, Complex)) || !(w = NAG_ALLOC(w_len, Complex)) || !(z = NAG_ALLOC(n * n, Complex)) ) { Vprintf("Allocation failure\n"); exit_status = -1; goto END; } /* Read H from data file */ for (i = 1; i <= n; ++i) { for (j = 1; j <= n; ++j) Vscanf(" ( %lf , %lf )", &H(i,j).re, &H(i,j).im); } Vscanf("%*[^\n] "); /* Calculate the eigenvalues and Schur factorization of H */ /* nag_zhseqr (f08psc). * Eigenvalues and Schur factorization of complex upper * Hessenberg matrix reduced from complex general matrix */ nag_zhseqr(order, Nag_Schur, Nag_InitZ, n, 1, n, h, pdh, w, z, pdz, &fail); if (fail.code != NE_NOERROR) { Vprintf("Error from nag_zhseqr (f08psc).\n%s\n", fail.message); exit_status = 1; goto END; } Vprintf(" Eigenvalues\n"); for (i = 1; i <= n; ++i) Vprintf("(%7.4f,%7.4f) ", w[i-1].re, w[i-1].im); Vprintf("\n\n"); /* Print Schur form */ /* nag_gen_complx_mat_print_comp (x04dbc). * Print complex general matrix (comprehensive) */ nag_gen_complx_mat_print_comp(order, Nag_GeneralMatrix, Nag_NonUnitDiag, n, n, h, pdh, Nag_BracketForm, "%7.4f", "Schur form", Nag_IntegerLabels, 0, Nag_IntegerLabels, 0, 80, 0, 0, &fail); if (fail.code != NE_NOERROR) { Vprintf("Error from nag_gen_complx_mat_print_comp (x04dbc).\n%s\n", fail.message); exit_status = 1; goto END; } /* Print Schur vectors */ Vprintf("\n"); /* nag_gen_complx_mat_print_comp (x04dbc), see above. */ nag_gen_complx_mat_print_comp(order, Nag_GeneralMatrix, Nag_NonUnitDiag, n, n, z, pdz, Nag_BracketForm, "%7.4f", "Schur vectors of H", Nag_IntegerLabels, 0, Nag_IntegerLabels, 0, 80, 0, 0, &fail); if (fail.code != NE_NOERROR) { Vprintf("Error from nag_gen_complx_mat_print_comp (x04dbc).\n%s\n", fail.message); exit_status = 1; goto END; } END: if (h) NAG_FREE(h); if (w) NAG_FREE(w); if (z) NAG_FREE(z); return exit_status; }