/* nag_quicksort (m01csc) Example Program. * * Copyright 1990 Numerical Algorithms Group. * * Mark 2 revised, 1992. * 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); double y = *((const double *) b); return(x < y?-1:(x == y?0:1)); } #ifdef __cplusplus } #endif #define VEC(I, J) vec[(I) *tdvec + J] int main(void) { Integer exit_status = 0, i, j, k, m, n, tdvec; double *vec = 0; NagError fail; INIT_FAIL(fail); /* Skip heading in data file */ scanf("%*[^\n]"); printf("nag_quicksort (m01csc) Example Program Results\n"); scanf("%ld", &m); scanf("%ld", &n); scanf("%ld", &k); if (m >= 1 && n >= 1 && k >= 1) { if (!(vec = NAG_ALLOC(m*n, double))) { printf("Allocation failure\n"); exit_status = -1; goto END; } tdvec = 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", &VEC(i, j)); /* nag_quicksort (m01csc). * Quicksort of set of values of arbitrary data type */ nag_quicksort((Pointer) &VEC(0, k-1), (size_t) m, sizeof(double), (ptrdiff_t)(sizeof(double)*n), compare, Nag_Ascending, &fail); if (fail.code != NE_NOERROR) { printf("Error from nag_quicksort (m01csc).\n%s\n", fail.message); exit_status = 1; goto END; } printf("\nMatrix with column %ld sorted \n", k); for (i = 0; i < m; ++i) { for (j = 0; j < n; ++j) printf(" %8.1f ", VEC(i, j)); printf("\n"); } END: if (vec) NAG_FREE(vec); return exit_status; }