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restore m_crossed* and create lemmas

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Signed-off-by: Lev Nachmanson <levnach@hotmail.com>
This commit is contained in:
Lev Nachmanson 2023-09-06 09:27:30 -07:00
parent 41f59cb1ed
commit 288e66de59
4 changed files with 32 additions and 33 deletions
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2
src/math/lp/lar_solver.cpp
View file

@ -2361,8 +2361,6 @@ namespace lp {
// dep is the reason for the new bound
void lar_solver::set_infeasible_column_and_witness(unsigned j, bool lower_bound, u_dependency* dep) {
bool was_feas = column_is_feasible(j);
bool in_heap = m_mpq_lar_core_solver.m_r_solver.inf_heap().contains(j);
SASSERT(m_crossed_bounds_deps == nullptr && m_crossed_bounds_deps == nullptr);
set_status(lp_status::INFEASIBLE);
m_crossed_bounds_column = j;

9
src/math/lp/lar_solver.h
View file

@ -79,7 +79,7 @@ class lar_solver : public column_namer {
stacked_value<simplex_strategy_enum> m_simplex_strategy;
// such can be found at the initialization step: u < l
lpvar m_crossed_bounds_column;
u_dependency* m_crossed_bounds_deps;
u_dependency* m_crossed_bounds_deps;
lar_core_solver m_mpq_lar_core_solver;
int_solver* m_int_solver = nullptr;
bool m_need_register_terms = false;
@ -142,6 +142,13 @@ class lar_solver : public column_namer {
inline void clear_columns_with_changed_bounds() { m_columns_with_changed_bounds.reset(); }
public:
void insert_to_columns_with_changed_bounds(unsigned j);
const u_dependency* crossed_bounds_deps() const { return m_crossed_bounds_deps;}
u_dependency*& crossed_bounds_deps() { return m_crossed_bounds_deps;}
lpvar crossed_bounds_column() const { return m_crossed_bounds_column; }
lpvar& crossed_bounds_column() { return m_crossed_bounds_column; }
private:
void update_column_type_and_bound_check_on_equal(unsigned j, const mpq& right_side, constraint_index ci, unsigned&);
void update_column_type_and_bound(unsigned j, const mpq& right_side, constraint_index ci);

49
src/math/lp/monomial_bounds.cpp
View file

@ -258,32 +258,30 @@ namespace nla {
}
}
bool monomial_bounds::unit_propagate() {
unsigned sz = 0;
vector<lpvar> monics_vars;
for (auto const& m : c().m_emons) {
monics_vars.push_back(m.var());
sz++;
}
unsigned l = this->random();
for (unsigned i = 0; i < sz; ++i) {
lpvar v = monics_vars[(i + l) % sz];
if (!unit_propagate(c().m_emons[v])) {
return false;
}
}
return true;
void monomial_bounds::unit_propagate() {
for (auto const& m : c().m_emons)
unit_propagate(m);
}
// returns false if and only if there is a conflict
bool monomial_bounds::unit_propagate(monic const& m) {
void monomial_bounds::check_for_conflict() {
if (c().lra.crossed_bounds_deps() != nullptr) {
new_lemma lemma(c(), "fixed-values");
lp::explanation ex;
c().lra.fill_explanation_from_crossed_bounds_column(ex);
lemma &= ex;
c().lra.crossed_bounds_deps() = nullptr;
c().lra.crossed_bounds_column() = null_lpvar;
c().lra.set_status(lp::lp_status::OPTIMAL);
}
}
void monomial_bounds::unit_propagate(monic const& m) {
m_propagated.reserve(m.var() + 1, false);
if (m_propagated[m.var()])
return true;
return;
if (!is_linear(m))
return true;
return;
c().trail().push(set_bitvector_trail(m_propagated, m.var()));
lpvar zero_fixed = null_lpvar, non_fixed = null_lpvar;
@ -303,8 +301,7 @@ namespace nla {
if (zero_fixed != null_lpvar) {
// the m.var() has to have a zero value
u_dependency* d = this->dep.mk_join(c().lra.get_column_lower_bound_witness(zero_fixed),
c().lra.get_column_upper_bound_witness(zero_fixed));
c().lra.get_column_upper_bound_witness(zero_fixed));
c().lra.update_column_type_and_bound(m.var(), lp::lconstraint_kind::EQ, mpq(0), d);
} else if (non_fixed != null_lpvar) {
u_dependency* d = nullptr;
@ -330,7 +327,6 @@ namespace nla {
bool strict = b.y.is_pos();
c().lra.update_column_type_and_bound(m.var(), strict ? lp::lconstraint_kind::GT : lp::lconstraint_kind::GE, k * b.x, d);
}
} else {
d = c().lra.get_column_upper_bound_witness(non_fixed);
if (d) {
@ -358,12 +354,9 @@ namespace nla {
SASSERT(k.is_pos() || k.is_neg());
// we have m = k: m.var() getting the bounds witnesses of all fixed variables
c().lra.update_column_type_and_bound(m.var(), lp::lconstraint_kind::EQ, k, d);
}
if (c().lra.get_status() == lp::lp_status::INFEASIBLE) {
TRACE("nla_solver", tout << "conflict in unit_propagate\n";);
return false;
}
return true;
check_for_conflict();
SASSERT (c().lra.get_status() != lp::lp_status::INFEASIBLE);
}
bool monomial_bounds::is_linear(monic const& m) {
unsigned non_fixed = 0;

5
src/math/lp/monomial_bounds.h
View file

@ -32,12 +32,13 @@ namespace nla {
// monomial propagation
bool_vector m_propagated;
bool unit_propagate(monic const& m);
void unit_propagate(monic const& m);
bool is_linear(monic const& m);
rational fixed_var_product(monic const& m);
public:
monomial_bounds(core* core);
void propagate();
bool unit_propagate();
void unit_propagate();
void check_for_conflict();
};
}