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fixes in branching

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Signed-off-by: Lev Nachmanson <levnach@hotmail.com>
This commit is contained in:
Lev Nachmanson 2020-04-26 16:12:54 -07:00
parent 236edad8dc
commit 530f77281c
9 changed files with 20 additions and 40 deletions
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18
src/math/lp/lar_solver.cpp
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@ -445,8 +445,7 @@ void lar_solver::set_costs_to_zero(const lar_term& term) {
void lar_solver::prepare_costs_for_r_solver(const lar_term & term) {
TRACE("lar_solver", print_term(term, tout << "prepare: ") << "\n";);
m_basic_columns_with_changed_cost.resize(m_mpq_lar_core_solver.m_r_x.size());
if (move_non_basic_columns_to_bounds())
find_feasible_solution();
move_non_basic_columns_to_bounds();
auto & rslv = m_mpq_lar_core_solver.m_r_solver;
rslv.set_using_infeas_costs(false);
lp_assert(costs_are_zeros_for_r_solver());
@ -464,17 +463,26 @@ void lar_solver::prepare_costs_for_r_solver(const lar_term & term) {
lp_assert(rslv.reduced_costs_are_correct_tableau());
}
bool lar_solver::move_non_basic_columns_to_bounds() {
bool feasible(lp_status st) {
return st == lp_status::FEASIBLE || st == lp_status::OPTIMAL;
}
void lar_solver::move_non_basic_columns_to_bounds() {
auto & lcs = m_mpq_lar_core_solver;
bool change = false;
bool feas = feasible(get_status());
for (unsigned j : lcs.m_r_nbasis) {
if (move_non_basic_column_to_bounds(j))
change = true;
}
if (settings().simplex_strategy() == simplex_strategy_enum::tableau_costs)
if (settings().simplex_strategy() == simplex_strategy_enum::tableau_costs && change)
update_x_and_inf_costs_for_columns_with_changed_bounds_tableau();
return change;
if (feas && change) {
find_feasible_solution();
SASSERT(feasible(get_status()));
}
}
bool lar_solver::move_non_basic_column_to_bounds(unsigned j) {