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fixed dio

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Signed-off-by: Lev Nachmanson <levnach@hotmail.com>
This commit is contained in:
Lev Nachmanson 2024-09-28 07:34:56 -07:00 committed by Lev Nachmanson
parent 5ac428fcc9
commit 52b0b8d5d5
1 changed files with 66 additions and 40 deletions
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106
src/math/lp/dioph_eq.cpp
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@ -7,7 +7,6 @@
namespace lp {
// This class represents a term with an added constant number c, in form sum {x_i*a_i} + c.
// int global_max_change_ = 100000; // 9 , 10
class dioph_eq::imp {
class term_o:public lar_term {
mpq m_c;
@ -162,7 +161,6 @@ namespace lp {
void init() {
unsigned n_of_rows = lra.A_r().row_count();
unsigned fn = 0;
m_conflict_index = -1;
m_infeas_explanation.clear();
@ -280,7 +278,7 @@ namespace lp {
}
void subs_k(const eprime_pair& e, unsigned k, term_o& t, std::queue<unsigned> & q) {
if (t.contains(k) == false) return;
SASSERT (t.contains(k));
mpq coeff = t.get_coeff(k); // need to copy it because the pointer value can be changed during the next loop
const mpq& k_coeff_in_e = e.m_e.get_coeff(k);
bool is_one = k_coeff_in_e.is_one();
@ -311,20 +309,17 @@ namespace lp {
unsigned k = q.front();
q.pop();
const eprime_pair& e = m_eprime[m_k2s[k]];
if (!t.contains(k)) {
continue;
}
TRACE("dioph_eq", tout << "k:" << k << " in: "; print_eprime_entry(m_k2s[k], tout) << std::endl;);
subs_k(e, k, t, q);
dep = lra.mk_join(dep, e.m_l);
TRACE("dioph_eq", tout << "substituted t:"; print_term_o(t, tout) << std::endl;);
TRACE("dioph_eq_dep", tout << "dep:"; print_dep(tout, dep) << std::endl;);
TRACE("dioph_eq", tout << "substituted t:"; print_term_o(t, tout) << std::endl;
tout << "\ndep:"; print_dep(tout, dep) << std::endl;);
}
}
lia_move tighten_with_S_push_pop() {
lra.push();
lia_move ret = tighten_with_S();
lra.pop();
return ret;
}
lia_move tighten_with_S() {
// following the pattern of int_cube
@ -335,15 +330,15 @@ namespace lp {
if (tighten_bounds_for_column(j)) {
change++;
}
if (!m_infeas_explanation.empty()) {
return lia_move::conflict;
}
}
if (!change)
return lia_move::undef;
// std::cout << "change " << change << std::endl;
auto st = lra.find_feasible_solution();
if (st != lp::lp_status::FEASIBLE && st != lp::lp_status::OPTIMAL) {
lra.get_infeasibility_explanation(m_infeas_explanation);
std::cout << "tighten_with_S: infeasible\n";
return lia_move::conflict;
}
return lia_move::undef;
@ -366,7 +361,7 @@ namespace lp {
u_dependency * dep = nullptr;
TRACE("dioph_eq", tout << "t:"; print_term_o(t, tout) << std::endl;
tout << "dep:"; print_dep(tout, dep) << std::endl;);
/*tout << "dep:"; print_dep(tout, dep) << std::endl;*/);
process_q_with_S(q, t, dep);
TRACE("dioph_eq", tout << "after process_q_with_S\n t:"; print_term_o(t, tout) << std::endl;
tout << "dep:"; print_dep(tout, dep) << std::endl;);
@ -374,9 +369,45 @@ namespace lp {
if (g.is_one()) {
TRACE("dioph_eq", tout << "g is one" << std::endl;);
return false;
}
} else if (g.is_zero()) {
handle_constant_term(t, j, dep);
if (!m_infeas_explanation.empty())
return true;
return false;
}
return tighten_bounds_for_term(t, g, j, dep);
}
void handle_constant_term(term_o& t, unsigned j, u_dependency* dep) {
if (t.c().is_zero()) {
return;
}
mpq rs;
bool is_strict;
u_dependency *b_dep = nullptr;
if (lra.has_upper_bound(j, b_dep, rs, is_strict)) {
if (t.c() > rs || is_strict && t.c() == rs) {
for (const auto& p: lra.flatten(dep)) {
m_infeas_explanation.push_back(p);
}
for (const auto& p: lra.flatten(b_dep)) {
m_infeas_explanation.push_back(p);
}
}
return;
}
if (lra.has_lower_bound(j, b_dep, rs, is_strict)) {
if (t.c() < rs || is_strict && t.c() == rs) {
for (const auto& p: lra.flatten(dep)) {
m_infeas_explanation.push_back(p);
}
for (const auto& p: lra.flatten(b_dep)) {
m_infeas_explanation.push_back(p);
}
}
}
}
// returns true if there is a change
// dep comes from the substitution with S
bool tighten_bounds_for_term(term_o& t, const mpq& g, unsigned j, u_dependency* dep) {
@ -384,36 +415,27 @@ namespace lp {
bool is_strict;
bool change = false;
u_dependency *b_dep = nullptr;
// if (global_max_change <= 0) {
// return change;
// }
SASSERT(!g.is_zero());
if (lra.has_upper_bound(j, b_dep, rs, is_strict)) {
TRACE("dioph_eq", tout << "tighten upper bound for x" << j << " with rs:" << rs << std::endl;);
rs = rs - t.c();
rs /= g;
rs = (rs - t.c()) / g;
TRACE("dioph_eq", tout << "tighten upper bound for x" << j << " with rs:" << rs << std::endl;);
if (!rs.is_int() || !t.c().is_zero()) {
if (!rs.is_int()) {
tighten_bound_for_term(t, g, j, lra.mk_join(dep, b_dep), rs, true);
change = true;
//global_max_change--;
}
}
// if (global_max_change <= 0) {
// return change;
// }
if (lra.has_lower_bound(j, b_dep, rs, is_strict)) {
TRACE("dioph_eq", tout << "tighten lower bound for x" << j << " with rs:" << rs << std::endl;);
rs = rs - t.c();
rs /= g;
rs = (rs - t.c()) / g;
TRACE("dioph_eq", tout << "tighten lower bound for x" << j << " with rs:" << rs << std::endl;);
if (!rs.is_int()|| !t.c().is_zero()) {
if (!rs.is_int()) {
tighten_bound_for_term(t, g, j, lra.mk_join(b_dep, dep), rs, false);
change = true;
//global_max_change--;
}
}
return change;
@ -426,17 +448,20 @@ namespace lp {
// t_ <= floor((upper_bound(j) - t.c())/g) = floor(ub)
//
// so xj = g*t_+t.c() <= g*floor(ub) + t.c() is new upper bound
// <= can be replaced with >= for lower bounds, with ceil instead of floor
mpq bound = g * (upper?floor(ub):ceil(ub))+t.c();
dep = lra.mk_join(dep, lra.get_column_upper_bound_witness(j));
lra.update_column_type_and_bound(j, lconstraint_kind::LE, bound, dep);
TRACE("dioph_eq", tout << "upper:" << upper << std::endl;
tout << "new " << (upper? "upper":"lower" ) << "bound:" << bound << std::endl;);
dep = lra.mk_join(dep, upper? lra.get_column_upper_bound_witness(j): lra.get_column_lower_bound_witness(j) );
SASSERT(upper && bound <= lra.get_upper_bound(j).x || !upper && bound >= lra.get_lower_bound(j).x);
lconstraint_kind kind = upper? lconstraint_kind::LE: lconstraint_kind::GE;
lra.update_column_type_and_bound(j, kind, bound, dep);
TRACE("dioph_eq",
tout << "new " << (upper? "upper":"lower" ) << "bound:" << bound << std::endl;
tout << "bound_dep:\n";print_dep(tout, dep) << std::endl;);
}
lia_move check() {
init();
while(m_f.size()) {
@ -445,12 +470,13 @@ namespace lp {
rewrite_eqs();
}
TRACE("dioph_eq", print_S(tout););
lia_move ret = tighten_with_S_push_pop();
lia_move ret = tighten_with_S();
if (ret == lia_move::conflict) {
return lia_move::conflict;
}
return lia_move::undef;
}
std::list<unsigned>::iterator pick_eh() {
return m_f.begin(); // TODO: make a smarter joice
}
@ -576,7 +602,7 @@ namespace lp {
std::ostream& print_eprime_entry(unsigned i, std::ostream& out) {
out << "m_eprime[" << i << "]:{\n";
print_term_o(m_eprime[i].m_e, out << "\tm_e:") << "," << std::endl;
print_dep(out<< "\tm_l:", m_eprime[i].m_l) << "\n}"<< std::endl;
// print_dep(out<< "\tm_l:", m_eprime[i].m_l) << "\n}"<< std::endl;
return out;
}
@ -606,7 +632,7 @@ namespace lp {
}
void explain(explanation& ex) {
if (m_conflict_index == -1) {
if (m_conflict_index == static_cast<unsigned>(-1)) {
SASSERT(!(lra.get_status() == lp_status::FEASIBLE || lra.get_status() == lp_status::OPTIMAL));
for (auto ci: m_infeas_explanation) {
ex.push_back(ci.ci());