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integrating diff opt

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2014-03-05 16:29:26 -08:00
parent 80ba830091
commit 99b4ce037d
10 changed files with 67 additions and 59 deletions
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24
src/opt/optsmt.cpp
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@ -124,7 +124,8 @@ namespace opt {
}
void optsmt::update_lower() {
m_s->maximize_objectives();
expr_ref_vector disj(m);
m_s->maximize_objectives(disj);
m_s->get_model(m_model);
set_max(m_lower, m_s->get_objective_values());
IF_VERBOSE(1,
@ -134,13 +135,7 @@ namespace opt {
verbose_stream() << "\n";
model_pp(verbose_stream(), *m_model);
);
expr_ref_vector disj(m);
expr_ref constraint(m);
for (unsigned i = 0; i < m_lower.size(); ++i) {
inf_eps const& v = m_lower[i];
disj.push_back(m_s->mk_gt(i, v));
}
expr_ref constraint(m);
constraint = m.mk_or(disj.size(), disj.c_ptr());
m_s->assert_expr(constraint);
}
@ -237,25 +232,23 @@ namespace opt {
lbool optsmt::basic_lex(unsigned obj_index) {
lbool is_sat = l_true;
expr_ref block(m);
expr_ref block(m), tmp(m);
while (is_sat == l_true && !m_cancel) {
is_sat = m_s->check_sat(0, 0);
if (is_sat != l_true) break;
m_s->maximize_objective(obj_index);
m_s->maximize_objective(obj_index, block);
m_s->get_model(m_model);
inf_eps obj = m_s->get_objective_value(obj_index);
if (obj > m_lower[obj_index]) {
m_lower[obj_index] = obj;
IF_VERBOSE(1, verbose_stream() << "(optsmt lower bound: " << obj << ")\n";);
for (unsigned i = obj_index+1; i < m_vars.size(); ++i) {
m_s->maximize_objective(i);
m_s->maximize_objective(i, tmp);
m_lower[i] = m_s->get_objective_value(i);
}
}
block = m_s->mk_gt(obj_index, obj);
m_s->assert_expr(block);
// TBD: only works for simplex
@ -289,14 +282,13 @@ namespace opt {
is_sat = m_s->check_sat(0, 0);
if (is_sat != l_true) break;
was_sat = true;
m_s->maximize_objective(obj_index);
m_s->maximize_objective(obj_index, block);
m_s->get_model(m_model);
inf_eps obj = m_s->get_objective_value(obj_index);
if (obj > m_lower[obj_index]) {
m_lower[obj_index] = obj;
IF_VERBOSE(1, verbose_stream() << "(optsmt lower bound: " << obj << ")\n";);
}
block = m_s->mk_gt(obj_index, obj);
m_s->assert_expr(block);
}
@ -347,10 +339,12 @@ namespace opt {
inf_eps optsmt::get_lower(unsigned i) const {
if (i >= m_lower.size()) return inf_eps();
return m_lower[i];
}
inf_eps optsmt::get_upper(unsigned i) const {
if (i >= m_upper.size()) return inf_eps();
return m_upper[i];
}