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Dual push crossover rank deficient #733

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Dual push crossover rank deficient #733

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18 changes: 15 additions & 3 deletions cpp/src/dual_simplex/crossover.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -502,7 +502,18 @@ i_t dual_push(const lp_problem_t<i_t, f_t>& lp,
std::vector<i_t> q(m);
std::vector<i_t> deficient;
std::vector<i_t> slacks_needed;
factorize_basis(lp.A, settings, basic_list, L, U, p, pinv, q, deficient, slacks_needed);
i_t rank = factorize_basis(lp.A, settings, basic_list, L, U, p, pinv, q, deficient, slacks_needed);
if (rank != m) {
settings.log.printf("Failed to factorize basis. rank %d m %d\n", rank, m);
basis_repair(lp.A, settings, deficient, slacks_needed, basic_list, nonbasic_list, vstatus);
if (factorize_basis(lp.A, settings, basic_list, L, U, p, pinv, q, deficient, slacks_needed) ==
-1) {
settings.log.printf("Failed to factorize basis after repair. rank %d m %d\n", rank, m);
return -1;
} else {
settings.log.printf("Basis repaired\n");
}
}
reorder_basic_list(q, basic_list);
// Reordering the basic list causes us to mess up the superbasic list index
// so we need to update it
Expand Down Expand Up @@ -1203,8 +1214,8 @@ crossover_status_t crossover(const lp_problem_t<i_t, f_t>& lp,
i_t primal_push_status = primal_push(
lp, settings, start_time, solution, ft, basic_list, nonbasic_list, superbasic_list, vstatus);
if (primal_push_status < 0) { return return_to_status(primal_push_status); }
print_crossover_info(lp, settings, vstatus, solution, "Primal push complete");
compute_dual_solution_from_basis(lp, ft, basic_list, nonbasic_list, solution.y, solution.z);
print_crossover_info(lp, settings, vstatus, solution, "Primal push complete");
} else {
settings.log.printf("No primal push needed. No superbasic variables\n");
}
Expand Down Expand Up @@ -1353,7 +1364,8 @@ crossover_status_t crossover(const lp_problem_t<i_t, f_t>& lp,
}
}
settings.log.debug("Num flips %d\n", num_flips);
solution = phase1_solution;
solution.y = phase1_solution.y;
solution.z = phase1_solution.z;
print_crossover_info(lp, settings, vstatus, solution, "Dual phase 1 complete");
std::vector<f_t> edge_norms;
dual::status_t status = dual_phase2(
Expand Down