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testing decomposition during pre-processing

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2014-01-02 16:05:26 -08:00
parent 8d0d123a4c
commit 3fa0e6f3fb
3 changed files with 174 additions and 158 deletions
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2
src/opt/opt_params.pyg
View file

@ -9,8 +9,6 @@ def_module_params('opt',
('print_model', BOOL, False, 'display model for satisfiable constraints'),
('debug_conflict', BOOL, False, 'debug conflict resolution'),
('wmaxsat_engine', SYMBOL, 'wmax', "weighted maxsat engine: 'wmax', 'iwmax' (iterative), 'bwmax' (bisection)"),
('pb_conflict_freq', UINT, 0, 'conflict frequency for pb theory'),
('pb_learn_comp', BOOL, True, 'learn complement literals'),
('elim_01', BOOL, True, 'eliminate 01 variables')
))

120
src/opt/weighted_maxsat.cpp
View file

@ -410,9 +410,6 @@ namespace opt {
if (m_engine == symbol("iwmax")) {
return iterative_solve();
}
if (m_engine == symbol("bwmax")) {
return bisection_solve();
}
if (m_engine == symbol("pwmax")) {
return pb_solve();
}
@ -509,7 +506,7 @@ namespace opt {
lbool result = l_false;
unsigned nsc = 0;
m_upper = cost;
while (log_cost <= cost && result == l_false) {
while (result == l_false) {
bound = wth().set_min_cost(log_cost);
s.push_core();
++nsc;
@ -520,6 +517,9 @@ namespace opt {
if (result == l_false) {
m_lower = log_cost;
}
if (log_cost > cost) {
break;
}
log_cost *= rational(2);
if (m_cancel) {
result = l_undef;
@ -560,50 +560,6 @@ namespace opt {
return is_sat;
}
lbool bisection_solve() {
TRACE("opt", tout << "weighted maxsat\n";);
scoped_ensure_theory wth(*this);
solver::scoped_push _s(s);
lbool is_sat = l_true;
bool was_sat = false;
expr_ref_vector bounds(m);
for (unsigned i = 0; i < m_soft.size(); ++i) {
wth().assert_weighted(m_soft[i].get(), m_weights[i]);
}
solver::scoped_push __s(s);
m_lower = rational::zero();
m_upper = wth().get_min_cost();
while (m_lower < m_upper && is_sat != l_undef) {
rational cost = div(m_upper + m_lower, rational(2));
bounds.push_back(wth().set_min_cost(cost));
is_sat = s.check_sat_core(1,bounds.c_ptr()+bounds.size()-1);
if (m_cancel) {
is_sat = l_undef;
}
switch(is_sat) {
case l_true: {
if (wth().is_optimal()) {
s.get_model(m_model);
}
expr_ref fml = wth().mk_block();
s.assert_expr(fml);
m_upper = wth().get_min_cost();
break;
}
case l_false: {
m_lower = cost;
IF_VERBOSE(1, verbose_stream() << "(wmaxsat.bwmax min cost: " << m_lower << ")\n";);
break;
}
case l_undef:
break;
}
}
if (was_sat) {
is_sat = l_true;
}
return is_sat;
}
// convert bounds constraint into pseudo-Boolean
@ -708,6 +664,12 @@ namespace opt {
m_lower = m_upper = rational::zero();
obj_map<expr, unsigned> ans_index;
#ifdef WPM2b
// change from CP'13
for (unsigned i = 0; i < s.get_num_assertions(); ++i) {
al.push_back(s.get_assertion(i));
}
#endif
vector<rational> amk;
vector<uint_set> sc;
for (unsigned i = 0; i < m_soft.size(); ++i) {
@ -796,7 +758,10 @@ namespace opt {
}
}
rational k;
std::cout << "new bound";
is_sat = new_bound(al, ws, bs, k);
std::cout << " " << k << "\n";
std::cout.flush();
if (is_sat != l_true) {
return is_sat;
}
@ -830,8 +795,7 @@ namespace opt {
al2.append(al);
// w_j*b_j > k
al2.push_back(m.mk_not(u.mk_le(ws.size(), ws.c_ptr(), bs.c_ptr(), k)));
is_sat = bound(al2, ws, bs, k);
return is_sat;
return bound(al2, ws, bs, k);
}
//
@ -843,8 +807,8 @@ namespace opt {
vector<rational> const& ws,
expr_ref_vector const& bs,
rational& k) {
expr_ref_vector nbs(m);
m_solver.push_core();
expr_ref_vector nbs(m);
opt_solver::scoped_push _sc(m_solver);
for (unsigned i = 0; i < al.size(); ++i) {
m_solver.assert_expr(al[i]);
}
@ -854,7 +818,6 @@ namespace opt {
m_imp->re_init(nbs, ws);
lbool is_sat = m_imp->pb_simplify_solve();
k = m_imp->m_lower;
m_solver.pop_core(1);
return is_sat;
}
@ -952,3 +915,54 @@ namespace opt {
};
#if 0
// The case m_lower = 0, m_upper = 1 is not handled correctly.
// cost becomes 0
lbool bisection_solve() {
TRACE("opt", tout << "weighted maxsat\n";);
scoped_ensure_theory wth(*this);
solver::scoped_push _s(s);
lbool is_sat = l_true;
bool was_sat = false;
expr_ref_vector bounds(m);
for (unsigned i = 0; i < m_soft.size(); ++i) {
wth().assert_weighted(m_soft[i].get(), m_weights[i]);
}
solver::scoped_push __s(s);
m_lower = rational::zero();
m_upper = wth().get_min_cost();
while (m_lower < m_upper && is_sat != l_undef) {
rational cost = div(m_upper + m_lower, rational(2));
bounds.push_back(wth().set_min_cost(cost));
is_sat = s.check_sat_core(1,bounds.c_ptr()+bounds.size()-1);
if (m_cancel) {
is_sat = l_undef;
}
switch(is_sat) {
case l_true: {
if (wth().is_optimal()) {
s.get_model(m_model);
}
expr_ref fml = wth().mk_block();
s.assert_expr(fml);
m_upper = wth().get_min_cost();
IF_VERBOSE(1, verbose_stream() << "(wmaxsat.bwmax max cost: " << m_upper << ")\n";);
break;
}
case l_false: {
m_lower = cost;
IF_VERBOSE(1, verbose_stream() << "(wmaxsat.bwmax min cost: " << m_lower << ")\n";);
break;
}
case l_undef:
break;
}
}
if (was_sat) {
is_sat = l_true;
}
return is_sat;
}
#endif