/* nag_zgbbrd (f08lsc) Example Program. * * Copyright 2001 Numerical Algorithms Group. * * Mark 7, 2001. */ #include #include #include #include int main(void) { /* Scalars */ Integer i, j, kl, ku, m, n, ncc, pdab, pdc, pdq, pdpt; Integer d_len, e_len; Integer exit_status = 0; NagError fail; Nag_OrderType order; /* Arrays */ Complex *ab = 0, *c = 0, *pt = 0, *q = 0; double *d = 0, *e = 0; #ifdef NAG_COLUMN_MAJOR #define AB(I, J) ab[(J - 1) * pdab + ku + I - J] order = Nag_ColMajor; #else #define AB(I, J) ab[(I - 1) * pdab + kl + J - I] order = Nag_RowMajor; #endif INIT_FAIL(fail); printf("nag_zgbbrd (f08lsc) Example Program Results\n"); /* Skip heading in data file */ scanf("%*[^\n] "); scanf("%ld%ld%ld%ld%ld%*[^\n] ", &m, &n, &kl, &ku, &ncc); #ifdef NAG_COLUMN_MAJOR pdab = kl + ku + 1; pdq = m; pdpt = n; pdc = m; #else pdab = kl + ku + 1; pdq = m; pdpt = n; pdc = MAX(1, ncc); #endif d_len = MIN(m, n); e_len = MIN(m, n) - 1; /* Allocate memory */ if (!(ab = NAG_ALLOC((kl+ku+1) * m, Complex)) || !(c = NAG_ALLOC(m * MAX(1, ncc), Complex)) || !(d = NAG_ALLOC(d_len, double)) || !(e = NAG_ALLOC(e_len, double)) || !(pt = NAG_ALLOC(n * n, Complex)) || !(q = NAG_ALLOC(m * m, Complex))) { printf("Allocation failure\n"); exit_status = -1; goto END; } /* Read A from data file */ for (i = 1; i <= m; ++i) { for (j = MAX(1, i - kl); j <= MIN(n, i + ku); ++j) scanf(" ( %lf , %lf )", &AB(i, j).re, &AB(i, j).im); } scanf("%*[^\n] "); /* Reduce A to bidiagonal form */ /* nag_zgbbrd (f08lsc). * Reduction of complex rectangular band matrix to upper * bidiagonal form */ nag_zgbbrd(order, Nag_DoNotForm, m, n, ncc, kl, ku, ab, pdab, d, e, q, pdq, pt, pdpt, c, pdc, &fail); if (fail.code != NE_NOERROR) { printf("Error from nag_zgbbrd (f08lsc).\n%s\n", fail.message); exit_status = 1; goto END; } /* Print bidiagonal form */ printf("\nDiagonal\n"); for (i = 1; i <= MIN(m, n); ++i) printf("%9.4f%s", d[i-1], i%8 == 0?"\n":" "); if (m >= n) printf("\nSuper-diagonal\n"); else printf("\nSub-diagonal\n"); for (i = 1; i <= MIN(m, n) - 1; ++i) printf("%9.4f%s", e[i-1], i%8 == 0?"\n":" "); printf("\n"); END: if (ab) NAG_FREE(ab); if (c) NAG_FREE(c); if (d) NAG_FREE(d); if (e) NAG_FREE(e); if (pt) NAG_FREE(pt); if (q) NAG_FREE(q); return exit_status; }