//Supporting routine for Quicksort int partition(int* a,int l,int r) { int i,j; int x; int len = r-l; //swap(a,l,r); // This is for part 2. For part 1 comment this line out // part 3 int pivot = choose_pivot(a, l, r); swap(a, l, pivot); x = a[l]; i = l+1; count1 = count1 + len; for(j=l+1;j<r+1;j++) { if(a[j] <= x) { swap(a,i,j); i++; } count2++; } swap(a,i-1,l); return(i-1); }
static T *seqpart(T *low, T *high) { T pivot; T h, l; T *curr_low = low; T *curr_high = high; pivot = choose_pivot(low, high); while (1) { while ((h = *curr_high) > pivot) curr_high--; while ((l = *curr_low) < pivot) curr_low++; if (curr_low >= curr_high) break; *curr_high-- = l; *curr_low++ = h; } /* * I don't know if this is really necessary. * The problem is that the pivot is not always the * first element, and the partition may be trivial. * However, if the partition is trivial, then * *high is the largest element, whence the following * code. */ if (curr_high < high) return curr_high; else return curr_high - 1UL; }
void quicksort(int m, int n) { int i, j, k; leaf_t key; if (m < n) { k = choose_pivot(m, n); swap(m, k); key = leafs[m]; i = m + 1; j = n; while (i <= j) { while ((i <= n) && (hilbert_ieee_cmp(3, leafs[i].pos, key.pos) <= 0)) i++; while ((j >= m) && (hilbert_ieee_cmp(3, leafs[j].pos, key.pos) > 0)) j--; if (i < j) swap(i, j); } // swap two elements swap(m, j); // recursively sort the lesser list quicksort(m, j - 1); quicksort(j + 1, n); } }
void qSort(int *x, int m, int n) { int key,i,j,k; if( m < n) { k = choose_pivot(m,n); swap(&x[m],&x[k]); key = x[m]; i = m+1; j = n; while(i <= j) { while((i <= n) && (x[i] <= key)) { comparisons++; i++; } while((j >= m) && (x[j] > key)) { comparisons++; j--; } if( i < j) swap(&x[i],&x[j]); } // swap two elements swap(&x[m],&x[j]); // recursively sort the lesser x qSort(x,m,j-1); qSort(x,j+1,n); } }
void quicksort(int list[],int m,int n) { int key,i,j,k; if( m < n) { k = choose_pivot(m,n); swap(&list[m],&list[k]); key = list[m]; i = m+1; j = n; while(i <= j) { while((i <= n) && (list[i] <= key)) i++; while((j >= m) && (list[j] > key)) j--; if( i < j) swap(&list[i],&list[j]); } swap(&list[m],&list[j]); quicksort(list,m,j-1); quicksort(list,j+1,n); } }
void quicksort(Entry list[],int m,int n) { int key,i,j,k; if( m < n) { k = choose_pivot(m,n); swap(&list[m],&list[k]); key = list[m].number; i = m+1; j = n; while(i <= j) { while((i <= n) && (list[i].number >= key)) i++; while((j >= m) && (list[j].number < key)) j--; if( i < j) swap(&list[i],&list[j]); } // swap two elements swap(&list[m],&list[j]); // recursively sort the lesser list quicksort(list,m,j-1); quicksort(list,j+1,n); } }
void quicksort(int list[],int m,int n) { int key,i,j,k; if( m < n) { k = choose_pivot(m,n); swap(&list[m],&list[k]); key = list[m]; i = m+1; j = n; while(i <= j) { while((i <= n) && (list[i] <= key)) i++; while((j >= m) && (list[j] > key)) j--; if( i < j) swap(&list[i],&list[j]); } /* swap two elements */ swap(&list[m],&list[j]); /* recursively sort the lesser list */ quicksort(list,m,j-1); quicksort(list,j+1,n); } }
int partition(int *a,int p,int r) { int i,j,x,temp,piv; //Declaring variables piv=choose_pivot(a,p,r); //Choosing pivot //Arranging pivot as first element temp=a[p]; a[p]=a[piv]; a[piv]=temp; i=p+1; j=r; x=a[p]; while(i<=j) //For i>j, Array is now partitioned { while((j>=p)&&(a[j]>x)) //Finding smaller element to the right of pivot { j--; } while((i<=r)&&(a[i]<=x)) //Finding larger element to the left of pivot { i++; } if(i<j) //Swapping position of wrongly placed elements { temp=a[j]; a[j]=a[i]; a[i]=temp; } } //Positioning the pivot correctly temp=a[p]; a[p]=a[j]; a[j]=temp; return j; //Returning the index of the pivot }
void quicksort(t_env *env) { t_elem *tmp; while (!is_ordered(env)) { env->pivot = choose_pivot(env); while (env->a_start->value < env->pivot) pushing_to_b(env); while (1) { tmp = env->a_start; while (tmp && tmp->value >= env->pivot) tmp = tmp->next; if (!tmp) break ; while (env->a_start->value < env->pivot) pushing_to_b(env); if (env->a_start->next && ASTA > ANEX && ANEX > env->pivot) move_sa(env); (!is_ordered(env)) ? move_ra(env) : 0; } } optimize_order(env); while (env->b_start) move_pa(env); }
void quicksort(int a[],int i,int j){ int p,m; if(i>=j) return ; c=c+j-i; m=choose_pivot(i,j); swap(&a[i],&a[m]); p=partition(a,i,j); quicksort(a,i,p-1); quicksort(a,p+1,j); }
void quickSort(int *vec, int begin, int end) { int pivot; /* begin = end -> vetor ordenado */ if(begin < end) { pivot = choose_pivot(vec, begin, end); quickSort(vec, begin, pivot - 1); //left sub-array quickSort(vec, pivot + 1, end); //right sub-array } }
void quick_sort(data_t A[], int n) { data_t pivot; int first_eq, first_gt; if (n<=1) { return; } /* array section is non-trivial */ pivot = choose_pivot(A, n); partition(A, n, &pivot, &first_eq, &first_gt); quick_sort(A, first_eq); quick_sort(A+first_gt, n-first_gt); }
static inline int partition (int *array, int lo, int hi) { int pivot = choose_pivot (array, lo, hi); int left = lo; int right = hi; for (;;) { while (array[++left] < pivot); while (array[--right] > pivot); if (left >= right) break; swap (array, left, right); } return left; }
void quicksort(ForwardIt first, ForwardIt last) { using T = typename std::iterator_traits<ForwardIt>::value_type; if(first == last) return; int a = 0; T pivot = *choose_pivot(first,last); ForwardIt middle1 = std::partition(first, last, [pivot, a](const T& em){ return em < pivot;}); ForwardIt middle2 = std::partition(middle1, last, [pivot](const T& em){ return !(pivot < em); }); quicksort(first, middle1); quicksort(middle2, last); }
static jnx_int32 partition(sortable_array *sa, jnx_int32 first, jnx_int32 last) { jnx_int32 pivot = choose_pivot(sa, first, last); if (pivot != first) { swap(sa, first, pivot); } jnx_int32 i = first + 1, j = first + 1; while (j <= last) { if (sa->cf(sa->array[j], sa->array[first]) < 0) { swap(sa, i, j); i++; } j++; } pivot = i - 1; swap(sa, first, pivot); return pivot; }
int partition(int A[], int left, int right) { int pivot_index = choose_pivot(A, left, right); int pivot_value = A[pivot_index]; swap(A, pivot_index, right); int store_index = left; for(int i=left; i <= right; i++) { if(A[i] <= pivot_value) { swap(A, i, store_index); store_index = store_index + 1; } } swap(A, store_index, right); // move pivot to its final place return store_index; }
//2596 21422 1475 24600 23311 void quickSort(int *arr, int start , int end){ if ((end - start) < 2) return ; int pivot = choose_pivot(start,end); //swap(arr+pivot,arr+end); int trav1,trav2; trav1 = trav2 = start; while(trav2 < end){ if (arr[trav2] < arr[end]){ if(trav2 != trav1) swap(arr+trav2,arr+trav1); trav1++; } trav2++; } swap(arr+trav1,arr+end); quickSort(arr,start,trav1-1); quickSort(arr,trav1+1,end); }
void quick_sort(std::vector<int> &a, int l, int r) { m1 += r - l; if (r <= l) { return; } m2 += r - l; int pi = choose_pivot(a, l, r); swap(&a[l], &a[pi]); pi = partition(a, l, r); if (l < pi - 1) { quick_sort(a, l, pi - 1); } if (pi + 1 < r) { quick_sort(a, pi + 1, r); } }
int permut(int* array, int begin, int end){ int pivot; /* * for this algorithm to work, the pivot must be the first element. * So, we swap it with the first element */ swap(array, choose_pivot(array, begin, end), begin); pivot = begin; while(begin != end){ if(array[begin] >= array[end]){ swap(array, begin,end); pivot = begin+end - pivot; } if(pivot == begin) end --; else begin++; } return begin; }
static void choose_pivot(struct csa *csa) { SPXLP *lp = csa->lp; int m = lp->m; int n = lp->n; double *l = lp->l; int *head = lp->head; SPXAT *at = csa->at; SPXNT *nt = csa->nt; double *beta = csa->beta; double *d = csa->d; SPYSE *se = csa->se; int *list = csa->list; double *rho = csa->work; double *trow = csa->work1; int nnn, try, k, p, q, t; xassert(csa->beta_st); xassert(csa->d_st); /* initial number of eligible basic variables */ nnn = csa->num; /* nothing has been chosen so far */ csa->p = 0; try = 0; try: /* choose basic variable xB[p] */ xassert(nnn > 0); try++; if (se == NULL) { /* dual Dantzig's rule */ p = spy_chuzr_std(lp, beta, nnn, list); } else { /* dual projected steepest edge */ p = spy_chuzr_pse(lp, se, beta, nnn, list); } xassert(1 <= p && p <= m); /* compute p-th row of inv(B) */ spx_eval_rho(lp, p, rho); /* compute p-th row of the simplex table */ if (at != NULL) spx_eval_trow1(lp, at, rho, trow); else spx_nt_prod(lp, nt, trow, 1, -1.0, rho); /* choose non-basic variable xN[q] */ k = head[p]; /* x[k] = xB[p] */ if (!csa->harris) q = spy_chuzc_std(lp, d, beta[p] < l[k] ? +1. : -1., trow, csa->tol_piv, .30 * csa->tol_dj, .30 * csa->tol_dj1); else q = spy_chuzc_harris(lp, d, beta[p] < l[k] ? +1. : -1., trow, csa->tol_piv, .35 * csa->tol_dj, .35 * csa->tol_dj1); /* either keep previous choice or accept new choice depending on * which one is better */ if (csa->p == 0 || q == 0 || fabs(trow[q]) > fabs(csa->trow[csa->q])) { csa->p = p; memcpy(&csa->trow[1], &trow[1], (n-m) * sizeof(double)); csa->q = q; } /* check if current choice is acceptable */ if (csa->q == 0 || fabs(csa->trow[csa->q]) >= 0.001) goto done; if (nnn == 1) goto done; if (try == 5) goto done; /* try to choose other xB[p] and xN[q] */ /* find xB[p] in the list */ for (t = 1; t <= nnn; t++) if (list[t] == p) break; xassert(t <= nnn); /* move xB[p] to the end of the list */ list[t] = list[nnn], list[nnn] = p; /* and exclude it from consideration */ nnn--; /* repeat the choice */ goto try; done: /* the choice has been made */ return; } /*********************************************************************** * display - display search progress * * This routine displays some information about the search progress * that includes: * * search phase; * * number of simplex iterations performed by the solver; * * original objective value (only on phase II); * * sum of (scaled) dual infeasibilities for original bounds; * * number of dual infeasibilities (phase I) or primal infeasibilities * (phase II); * * number of basic factorizations since last display output. */ static void display(struct csa *csa, int spec) { SPXLP *lp = csa->lp; int m = lp->m; int n = lp->n; int *head = lp->head; char *flag = lp->flag; double *l = csa->l; /* original lower bounds */ double *u = csa->u; /* original upper bounds */ double *beta = csa->beta; double *d = csa->d; int j, k, nnn; double sum; /* check if the display output should be skipped */ if (csa->msg_lev < GLP_MSG_ON) goto skip; if (csa->out_dly > 0 && 1000.0 * xdifftime(xtime(), csa->tm_beg) < csa->out_dly) goto skip; if (csa->it_cnt == csa->it_dpy) goto skip; if (!spec && csa->it_cnt % csa->out_frq != 0) goto skip; /* display search progress depending on search phase */ switch (csa->phase) { case 1: /* compute sum and number of (scaled) dual infeasibilities * for original bounds */ sum = 0.0, nnn = 0; for (j = 1; j <= n-m; j++) { k = head[m+j]; /* x[k] = xN[j] */ if (d[j] > 0.0) { /* xN[j] should have lower bound */ if (l[k] == -DBL_MAX) { sum += d[j]; if (d[j] > +1e-7) nnn++; } } else if (d[j] < 0.0) { /* xN[j] should have upper bound */ if (u[k] == +DBL_MAX) { sum -= d[j]; if (d[j] < -1e-7) nnn++; } } } /* on phase I variables have artificial bounds which are * meaningless for original LP, so corresponding objective * function value is also meaningless */ xprintf(" %6d: %23s inf = %11.3e (%d)", csa->it_cnt, "", sum, nnn); break; case 2: /* compute sum of (scaled) dual infeasibilities */ sum = 0.0, nnn = 0; for (j = 1; j <= n-m; j++) { k = head[m+j]; /* x[k] = xN[j] */ if (d[j] > 0.0) { /* xN[j] should have its lower bound active */ if (l[k] == -DBL_MAX || flag[j]) sum += d[j]; } else if (d[j] < 0.0) { /* xN[j] should have its upper bound active */ if (l[k] != u[k] && !flag[j]) sum -= d[j]; } } /* compute number of primal infeasibilities */ nnn = spy_chuzr_sel(lp, beta, csa->tol_bnd, csa->tol_bnd1, NULL); xprintf("#%6d: obj = %17.9e inf = %11.3e (%d)", csa->it_cnt, (double)csa->dir * spx_eval_obj(lp, beta), sum, nnn); break; default: xassert(csa != csa); } if (csa->inv_cnt) { /* number of basis factorizations performed */ xprintf(" %d", csa->inv_cnt); csa->inv_cnt = 0; } xprintf("\n"); csa->it_dpy = csa->it_cnt; skip: return; } /*********************************************************************** * spy_dual - driver to dual simplex method * * This routine is a driver to the two-phase dual simplex method. * * On exit this routine returns one of the following codes: * * 0 LP instance has been successfully solved. * * GLP_EOBJLL * Objective lower limit has been reached (maximization). * * GLP_EOBJUL * Objective upper limit has been reached (minimization). * * GLP_EITLIM * Iteration limit has been exhausted. * * GLP_ETMLIM * Time limit has been exhausted. * * GLP_EFAIL * The solver failed to solve LP instance. */ static int dual_simplex(struct csa *csa) { /* dual simplex method main logic routine */ SPXLP *lp = csa->lp; int m = lp->m; int n = lp->n; double *l = lp->l; double *u = lp->u; int *head = lp->head; SPXNT *nt = csa->nt; double *beta = csa->beta; double *d = csa->d; SPYSE *se = csa->se; int *list = csa->list; double *trow = csa->trow; double *tcol = csa->tcol; double *pi = csa->work; int msg_lev = csa->msg_lev; double tol_bnd = csa->tol_bnd; double tol_bnd1 = csa->tol_bnd1; double tol_dj = csa->tol_dj; double tol_dj1 = csa->tol_dj1; int j, k, p_flag, refct, ret; check_flags(csa); loop: /* main loop starts here */ /* compute factorization of the basis matrix */ if (!lp->valid) { double cond; ret = spx_factorize(lp); csa->inv_cnt++; if (ret != 0) { if (msg_lev >= GLP_MSG_ERR) xprintf("Error: unable to factorize the basis matrix (%d" ")\n", ret); csa->p_stat = csa->d_stat = GLP_UNDEF; ret = GLP_EFAIL; goto fini; } /* check condition of the basis matrix */ cond = bfd_condest(lp->bfd); if (cond > 1.0 / DBL_EPSILON) { if (msg_lev >= GLP_MSG_ERR) xprintf("Error: basis matrix is singular to working prec" "ision (cond = %.3g)\n", cond); csa->p_stat = csa->d_stat = GLP_UNDEF; ret = GLP_EFAIL; goto fini; } if (cond > 0.001 / DBL_EPSILON) { if (msg_lev >= GLP_MSG_ERR) xprintf("Warning: basis matrix is ill-conditioned (cond " "= %.3g)\n", cond); } /* invalidate basic solution components */ csa->beta_st = csa->d_st = 0; } /* compute reduced costs of non-basic variables d = (d[j]) */ if (!csa->d_st) { spx_eval_pi(lp, pi); for (j = 1; j <= n-m; j++) d[j] = spx_eval_dj(lp, pi, j); csa->d_st = 1; /* just computed */ /* determine the search phase, if not determined yet (this is * performed only once at the beginning of the search for the * original bounds) */ if (!csa->phase) { j = check_feas(csa, 0.97 * tol_dj, 0.97 * tol_dj1, 1); if (j > 0) { /* initial basic solution is dual infeasible and cannot * be recovered */ /* start to search for dual feasible solution */ set_art_bounds(csa); csa->phase = 1; } else { /* initial basic solution is either dual feasible or its * dual feasibility has been recovered */ /* start to search for optimal solution */ csa->phase = 2; } } /* make sure that current basic solution is dual feasible */ j = check_feas(csa, tol_dj, tol_dj1, 0); if (j) { /* dual feasibility is broken due to excessive round-off * errors */ if (bfd_get_count(lp->bfd)) { /* try to provide more accuracy */ lp->valid = 0; goto loop; } if (msg_lev >= GLP_MSG_ERR) xprintf("Warning: numerical instability (dual simplex, p" "hase %s)\n", csa->phase == 1 ? "I" : "II"); if (csa->dualp) { /* do not continue the search; report failure */ csa->p_stat = csa->d_stat = GLP_UNDEF; ret = -1; /* special case of GLP_EFAIL */ goto fini; } /* try to recover dual feasibility */ j = check_feas(csa, 0.97 * tol_dj, 0.97 * tol_dj1, 1); if (j > 0) { /* dual feasibility cannot be recovered (this may happen * only on phase II) */ xassert(csa->phase == 2); /* restart to search for dual feasible solution */ set_art_bounds(csa); csa->phase = 1; } } } /* at this point the search phase is determined */ xassert(csa->phase == 1 || csa->phase == 2); /* compute values of basic variables beta = (beta[i]) */ if (!csa->beta_st) { spx_eval_beta(lp, beta); csa->beta_st = 1; /* just computed */ } /* reset the dual reference space, if necessary */ if (se != NULL && !se->valid) spy_reset_refsp(lp, se), refct = 1000; /* at this point the basis factorization and all basic solution * components are valid */ xassert(lp->valid && csa->beta_st && csa->d_st); check_flags(csa); #if CHECK_ACCURACY /* check accuracy of current basic solution components (only for * debugging) */ check_accuracy(csa); #endif /* check if the objective limit has been reached */ if (csa->phase == 2 && csa->obj_lim != DBL_MAX && spx_eval_obj(lp, beta) >= csa->obj_lim) { if (csa->beta_st != 1) csa->beta_st = 0; if (csa->d_st != 1) csa->d_st = 0; if (!(csa->beta_st && csa->d_st)) goto loop; display(csa, 1); if (msg_lev >= GLP_MSG_ALL) xprintf("OBJECTIVE %s LIMIT REACHED; SEARCH TERMINATED\n", csa->dir > 0 ? "UPPER" : "LOWER"); csa->num = spy_chuzr_sel(lp, beta, tol_bnd, tol_bnd1, list); csa->p_stat = (csa->num == 0 ? GLP_FEAS : GLP_INFEAS); csa->d_stat = GLP_FEAS; ret = (csa->dir > 0 ? GLP_EOBJUL : GLP_EOBJLL); goto fini; } /* check if the iteration limit has been exhausted */ if (csa->it_cnt - csa->it_beg >= csa->it_lim) { if (csa->beta_st != 1) csa->beta_st = 0; if (csa->d_st != 1) csa->d_st = 0; if (!(csa->beta_st && csa->d_st)) goto loop; display(csa, 1); if (msg_lev >= GLP_MSG_ALL) xprintf("ITERATION LIMIT EXCEEDED; SEARCH TERMINATED\n"); if (csa->phase == 1) { set_orig_bounds(csa); check_flags(csa); spx_eval_beta(lp, beta); } csa->num = spy_chuzr_sel(lp, beta, tol_bnd, tol_bnd1, list); csa->p_stat = (csa->num == 0 ? GLP_FEAS : GLP_INFEAS); csa->d_stat = (csa->phase == 1 ? GLP_INFEAS : GLP_FEAS); ret = GLP_EITLIM; goto fini; } /* check if the time limit has been exhausted */ if (1000.0 * xdifftime(xtime(), csa->tm_beg) >= csa->tm_lim) { if (csa->beta_st != 1) csa->beta_st = 0; if (csa->d_st != 1) csa->d_st = 0; if (!(csa->beta_st && csa->d_st)) goto loop; display(csa, 1); if (msg_lev >= GLP_MSG_ALL) xprintf("TIME LIMIT EXCEEDED; SEARCH TERMINATED\n"); if (csa->phase == 1) { set_orig_bounds(csa); check_flags(csa); spx_eval_beta(lp, beta); } csa->num = spy_chuzr_sel(lp, beta, tol_bnd, tol_bnd1, list); csa->p_stat = (csa->num == 0 ? GLP_FEAS : GLP_INFEAS); csa->d_stat = (csa->phase == 1 ? GLP_INFEAS : GLP_FEAS); ret = GLP_EITLIM; goto fini; } /* display the search progress */ display(csa, 0); /* select eligible basic variables */ switch (csa->phase) { case 1: csa->num = spy_chuzr_sel(lp, beta, 1e-8, 0.0, list); break; case 2: csa->num = spy_chuzr_sel(lp, beta, tol_bnd, tol_bnd1, list); break; default: xassert(csa != csa); } /* check for optimality */ if (csa->num == 0) { if (csa->beta_st != 1) csa->beta_st = 0; if (csa->d_st != 1) csa->d_st = 0; if (!(csa->beta_st && csa->d_st)) goto loop; /* current basis is optimal */ display(csa, 1); switch (csa->phase) { case 1: /* check for dual feasibility */ set_orig_bounds(csa); check_flags(csa); if (check_feas(csa, tol_dj, tol_dj1, 0) == 0) { /* dual feasible solution found; switch to phase II */ csa->phase = 2; xassert(!csa->beta_st); goto loop; } /* no dual feasible solution exists */ if (msg_lev >= GLP_MSG_ALL) xprintf("LP HAS NO DUAL FEASIBLE SOLUTION\n"); spx_eval_beta(lp, beta); csa->num = spy_chuzr_sel(lp, beta, tol_bnd, tol_bnd1, list); csa->p_stat = (csa->num == 0 ? GLP_FEAS : GLP_INFEAS); csa->d_stat = GLP_NOFEAS; ret = 0; goto fini; case 2: /* optimal solution found */ if (msg_lev >= GLP_MSG_ALL) xprintf("OPTIMAL LP SOLUTION FOUND\n"); csa->p_stat = csa->d_stat = GLP_FEAS; ret = 0; goto fini; default: xassert(csa != csa); } } /* choose xB[p] and xN[q] */ choose_pivot(csa); /* check for dual unboundedness */ if (csa->q == 0) { if (csa->beta_st != 1) csa->beta_st = 0; if (csa->d_st != 1) csa->d_st = 0; if (!(csa->beta_st && csa->d_st)) goto loop; display(csa, 1); switch (csa->phase) { case 1: /* this should never happen */ if (msg_lev >= GLP_MSG_ERR) xprintf("Error: dual simplex failed\n"); csa->p_stat = csa->d_stat = GLP_UNDEF; ret = GLP_EFAIL; goto fini; case 2: /* dual unboundedness detected */ if (msg_lev >= GLP_MSG_ALL) xprintf("LP HAS NO PRIMAL FEASIBLE SOLUTION\n"); csa->p_stat = GLP_NOFEAS; csa->d_stat = GLP_FEAS; ret = 0; goto fini; default: xassert(csa != csa); } } /* compute q-th column of the simplex table */ spx_eval_tcol(lp, csa->q, tcol); /* FIXME: tcol[p] and trow[q] should be close to each other */ xassert(tcol[csa->p] != 0.0); /* update values of basic variables for adjacent basis */ k = head[csa->p]; /* x[k] = xB[p] */ p_flag = (l[k] != u[k] && beta[csa->p] > u[k]); spx_update_beta(lp, beta, csa->p, p_flag, csa->q, tcol); csa->beta_st = 2; /* update reduced costs of non-basic variables for adjacent * basis */ if (spx_update_d(lp, d, csa->p, csa->q, trow, tcol) <= 1e-9) { /* successful updating */ csa->d_st = 2; } else { /* new reduced costs are inaccurate */ csa->d_st = 0; } /* update steepest edge weights for adjacent basis, if used */ if (se != NULL) { if (refct > 0) { if (spy_update_gamma(lp, se, csa->p, csa->q, trow, tcol) <= 1e-3) { /* successful updating */ refct--; } else { /* new weights are inaccurate; reset reference space */ se->valid = 0; } } else { /* too many updates; reset reference space */ se->valid = 0; } } /* update matrix N for adjacent basis, if used */ if (nt != NULL) spx_update_nt(lp, nt, csa->p, csa->q); /* change current basis header to adjacent one */ spx_change_basis(lp, csa->p, p_flag, csa->q); /* and update factorization of the basis matrix */ if (csa->p > 0) spx_update_invb(lp, csa->p, head[csa->p]); /* dual simplex iteration complete */ csa->it_cnt++; goto loop; fini: return ret; }