/* nag_reorder_vector (m01esc) Example Program. * * Copyright 1990 Numerical Algorithms Group. * * Mark 2 revised, 1992. * Mark 5 revised, 1998. * Mark 7 revised, 2001. * Mark 8 revised, 2004. * */ #include #include #include #include #include #ifdef __cplusplus extern "C" { #endif static Integer NAG_CALL compare(const Nag_Pointer a, const Nag_Pointer b) { double x = *((const double *) a) - *((const double *) b); return(x < 0.0?-1:(x == 0.0?0:1)); } #ifdef __cplusplus } #endif #define A(I, J) a[(I) *tda + J] int main(void) { Integer exit_status = 0, tda; NagError fail; double *a = 0; size_t i, *indices = 0, j, k, m, n; unsigned long m_ulong, n_ulong, k_ulong; INIT_FAIL(fail); /* Skip heading in data file */ scanf("%*[^\n]"); printf("nag_reorder_vector (m01esc) Example Program Results\n"); scanf("%u%u%"NAG_UFMT, &m_ulong, &n_ulong, &k_ulong); m = (size_t)m_ulong; n = (size_t)n_ulong; k = (size_t)k_ulong; if (m >= 1 && n >= 1 && k >= 1 && k <= n) { if (!(a = NAG_ALLOC(m*n, double)) || !(indices = NAG_ALLOC(m, size_t))) { printf("Allocation failure\n"); exit_status = -1; goto END; } tda = n; } else { printf("Invalid m or n or k.\n"); exit_status = 1; return exit_status; } for (i = 0; i < m; ++i) for (j = 0; j < n; ++j) scanf("%lf", &A(i, j)); /* nag_rank_sort (m01dsc). * Rank sort of set of values of arbitrary data type */ nag_rank_sort((Pointer) &A(0, k-1), m, (ptrdiff_t)(n*sizeof(double)), compare, Nag_Ascending, indices, &fail); if (fail.code != NE_NOERROR) { printf("Error from nag_rank_sort (m01dsc).\n%s\n", fail.message); exit_status = 1; goto END; } /* nag_make_indices (m01zac). * Inverts a permutation converting a rank vector to an * index vector or vice versa */ nag_make_indices(indices, m, &fail); if (fail.code != NE_NOERROR) { printf("Error from nag_make_indices (m01zac).\n%s\n", fail.message); exit_status = 1; goto END; } for (j = 0; j < n; ++j) { /* nag_reorder_vector (m01esc). * Reorders set of values of arbitrary data type into the * order specified by a set of indices */ nag_reorder_vector((Pointer) &A(0, j), m, sizeof(double), (ptrdiff_t)(n*sizeof(double)), indices, &fail); if (fail.code != NE_NOERROR) { printf("Error from nag_reorder_vector (m01esc).\n%s\n", fail.message); exit_status = 1; goto END; } } printf("\nMatrix with column %u sorted\n", (unsigned long)k); for (i = 0; i < m; ++i) { for (j = 0; j < n; ++j) printf(" %7.1f ", A(i, j)); printf("\n"); } END: if (a) NAG_FREE(a); if (indices) NAG_FREE(indices); return exit_status; }