mirrors/z3
3
0
Fork 0
mirror of https://github.com/Z3Prover/z3 synced 2025-04-27 10:55:50 +00:00
Code Activity

fix term_o init

Browse source 
Signed-off-by: Lev Nachmanson <levnach@hotmail.com>
This commit is contained in:
Lev Nachmanson 2024-08-26 13:34:28 -10:00 • committed by Lev Nachmanson
parent a796d48264
commit 245d448c66
1 changed files with 30 additions and 20 deletions
Download patch file Download diff file Expand all files Collapse all files

50
src/math/lp/dioph_eq.cpp
View file

@ -18,6 +18,7 @@ namespace lp {
ret.add_monomial(p.coeff(), p.j());
}
ret.c() = c();
ret.j() = j();
return ret;
}
const mpq& c() const { return m_c; }
@ -58,6 +59,14 @@ namespace lp {
}
};
std::ostream& print_S(std::ostream & out) const {
out << "S:\n";
for (unsigned i : m_s) {
out << "x" << m_eprime[i].m_e.j() << " ->\n";
print_eprime_entry(i, out);
}
return out;
}
std::ostream& print_lar_term_L(const lar_term & t, std::ostream & out) const {
return print_linear_combination_customized(t.coeffs_as_vector(), [](int j)->std::string {return "y"+std::to_string(j);}, out );
@ -66,6 +75,7 @@ namespace lp {
std::ostream& print_term_o(term_o const& term, std::ostream& out) const {
if (term.size() == 0) {
out << "0";
out << ", j():"<< term.j();
return out;
}
bool first = true;
@ -90,6 +100,7 @@ namespace lp {
} else {
out << "x~" << (UINT_MAX - p.j()); // ~ is for a fresh variable
}
}
if (!term.c().is_zero()) {
@ -98,6 +109,7 @@ namespace lp {
else
out << " - " << -term.c();
}
out << ", j():"<< term.j();
return out;
}
@ -107,7 +119,7 @@ namespace lp {
*/
struct eprime_pair {
term_o m_e;
lar_term m_l; // this term keeps the history of m_e : originally m_l = k, where k is the index of eprime_pair in m_eprime
lar_term m_l; // this term keeps the history of m_e : originally m_l is i, the index of row m_e was constructed from
};
vector<eprime_pair> m_eprime;
@ -133,16 +145,16 @@ namespace lp {
imp(int_solver& lia, lar_solver& lra): lia(lia), lra(lra) {}
term_o row_to_term(const row_strip<mpq>& row) const {
term_o t;
const auto lcm = get_denominators_lcm(row);
term_o t;
for (const auto & p: row)
if (lia.is_fixed(p.var()))
t.c() += lia.lower_bound(p.var()).x;
else
t.add_monomial(lcm * p.coeff(), p.var());
t.c() *= lcm;
return t;
}
void init() {
unsigned n_of_rows = lra.A_r().row_count();
@ -160,17 +172,12 @@ namespace lp {
for (unsigned i = 0; i < n_of_rows; i++) {
auto & row = lra.get_row(i);
if (!all_vars_are_int(row)) continue;
const auto lcm = get_denominators_lcm(row);
term_o t = row_to_term(row);
t.j() = i; //highjack this field to point to the original tableau row, TODO - is it used?
TRACE("dioph_eq", tout << "row = "; lra.print_row(row, tout) << std::endl;);
unsigned lvar = static_cast<unsigned>(m_f.size());
lar_term lt = lar_term(lvar);
eprime_pair pair = {t, lt};
TRACE("dioph_eq", tout << "row = "; lra.print_row(row, tout) << std::endl;);
eprime_pair pair = {t, lar_term(i)};
m_f.push_back(m_f.size());
m_eprime.push_back(pair);
m_f.push_back(lvar);
TRACE("dioph_eq", print_eprime_entry(lvar, tout););
TRACE("dioph_eq", print_eprime_entry(m_f.size() - 1, tout););
}
}
@ -236,17 +243,17 @@ namespace lp {
}
lia_move check() {
std::cout << "ddd = " << ++lp_settings::ddd << std::endl;
if (lp::lp_settings::ddd == 5) {
enable_trace("dioph_eq");
enable_trace("dioph_eq_fresh");
}
// if (lp::lp_settings::ddd == 5) {
// enable_trace("dioph_eq");
// enable_trace("dioph_eq_fresh");
// }
init();
while(m_f.size()) {
if (!normalize_by_gcd())
return lia_move::conflict;
rewrite_eqs();
}
TRACE("dioph_eq", print_S(tout););
return lia_move::sat;
}
std::list<unsigned>::iterator pick_eh() {
@ -346,7 +353,7 @@ namespace lp {
TRACE("dioph_eq", tout << "xt_subs: x~"<< fresh_index(xt) << " -> "; print_term_o(xt_subs, tout) << std::endl;);
m_sigma.insert(xt, xt_subs);
}
std::ostream& print_eprime_entry(unsigned i, std::ostream& out) {
std::ostream& print_eprime_entry(unsigned i, std::ostream& out) const {
out << "m_eprime[" << i << "]:{\n";
print_term_o(m_eprime[i].m_e, out << "\tm_e:") << "," << std::endl;
print_lar_term_L(m_eprime[i].m_l, out<< "\tm_l:") << "\n}"<< std::endl;
@ -355,12 +362,14 @@ namespace lp {
// this is the step 6 or 7 of the algorithm
void rewrite_eqs() {
auto eh_it = pick_eh();
auto eprime_entry = m_eprime[*eh_it];
auto& eprime_entry = m_eprime[*eh_it];
TRACE("dioph_eq", print_eprime_entry(*eh_it, tout););
term_o& eh = eprime_entry.m_e;
auto [ahk, k, k_sign] = find_minimal_abs_coeff(eh);
TRACE("dioph_eq", tout << "ahk:" << ahk << ", k:" << k << ", k_sign:" << k_sign << std::endl;);
if (ahk.is_one()) {
eprime_entry.m_e.j() = k;
TRACE("dioph_eq", tout << "push to S:\n"; print_eprime_entry(*eh_it, tout););
m_s.push_back(*eh_it);
m_f.erase(eh_it);
eliminate_var(eprime_entry, k , k_sign);
@ -376,7 +385,8 @@ namespace lp {
auto & ep = m_eprime[m_conflict_index];
u_dependency* dep = nullptr;
for (const auto & pl : ep.m_l) {
for (const auto & p : lra.get_row(m_eprime[pl.j()].m_e.j()))
unsigned row_index = pl.j();
for (const auto & p : lra.get_row(row_index))
if (lra.column_is_fixed(p.var()))
lra.explain_fixed_column(p.var(), ex);
}