mirrors/z3
3
0
Fork 0
mirror of https://github.com/Z3Prover/z3 synced 2025-04-23 17:15:31 +00:00
Code Activity

fixes in max term with tableau

Browse source 
Signed-off-by: Lev Nachmanson <levnach@hotmail.com>
This commit is contained in:
Lev Nachmanson 2020-03-18 13:47:43 -07:00
parent b14f5aab83
commit 6c5d7fbe96
3 changed files with 14 additions and 5 deletions
Download patch file Download diff file Expand all files Collapse all files

14
src/math/lp/lar_solver.cpp
View file

@ -392,6 +392,7 @@ bool lar_solver::maximize_term_on_tableau(const lar_term & term,
m_mpq_lar_core_solver.solve();
lp_status st = m_mpq_lar_core_solver.m_r_solver.get_status();
TRACE("lar_solver", tout << st << "\n";);
SASSERT( m_mpq_lar_core_solver.m_r_solver.calc_current_x_is_feasible_include_non_basis());
if (st == lp_status::UNBOUNDED) {
return false;
}
@ -442,6 +443,8 @@ 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.clear();
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();
auto & rslv = m_mpq_lar_core_solver.m_r_solver;
@ -457,6 +460,7 @@ void lar_solver::prepare_costs_for_r_solver(const lar_term & term) {
else
rslv.update_reduced_cost_for_basic_column_cost_change(- p.coeff(), j);
}
rslv.m_costs_backup = rslv.m_costs;
lp_assert(rslv.reduced_costs_are_correct_tableau());
}
@ -525,8 +529,8 @@ bool lar_solver::maximize_term_on_corrected_r_solver(lar_term & term,
switch (settings().simplex_strategy()) {
case simplex_strategy_enum::tableau_rows:
prepare_costs_for_r_solver(term);
settings().simplex_strategy() = simplex_strategy_enum::tableau_costs;
prepare_costs_for_r_solver(term);
ret = maximize_term_on_tableau(term, term_max);
settings().simplex_strategy() = simplex_strategy_enum::tableau_rows;
set_costs_to_zero(term);
@ -818,9 +822,11 @@ void lar_solver::update_x_and_inf_costs_for_columns_with_changed_bounds_tableau(
update_x_and_inf_costs_for_column_with_changed_bounds(j);
if (tableau_with_costs()) {
for (unsigned j : m_basic_columns_with_changed_cost.m_index)
m_mpq_lar_core_solver.m_r_solver.update_inf_cost_for_column_tableau(j);
lp_assert(m_mpq_lar_core_solver.m_r_solver.reduced_costs_are_correct_tableau());
if (m_mpq_lar_core_solver.m_r_solver.m_using_infeas_costs) {
for (unsigned j : m_basic_columns_with_changed_cost.m_index)
m_mpq_lar_core_solver.m_r_solver.update_inf_cost_for_column_tableau(j);
lp_assert(m_mpq_lar_core_solver.m_r_solver.reduced_costs_are_correct_tableau());
}
}
}

4
src/math/lp/lp_primal_core_solver_tableau_def.h
View file

@ -161,7 +161,7 @@ unsigned lp_primal_core_solver<T, X>::solve_with_tableau() {
break;
case lp_status::UNBOUNDED:
if (this->current_x_is_infeasible()) {
init_reduced_costs();
init_reduced_costs_tableau();
this->set_status(lp_status::UNKNOWN);
}
break;
@ -385,7 +385,9 @@ update_x_tableau(unsigned entering, const X& delta) {
template <typename T, typename X> void lp_primal_core_solver<T, X>::
update_inf_cost_for_column_tableau(unsigned j) {
lp_assert(this->m_settings.simplex_strategy() != simplex_strategy_enum::tableau_rows);
lp_assert(this->m_using_infeas_costs);
T new_cost = get_infeasibility_cost_for_column(j);
T delta = this->m_costs[j] - new_cost;
if (is_zero(delta))