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add sls test to wmax

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2014-03-18 21:30:45 -07:00
parent 7b0ffc9108
commit 78975827b2
3 changed files with 83 additions and 24 deletions
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94
src/opt/pb_sls.cpp
View file

@ -61,19 +61,25 @@ namespace smt {
vector<clause> m_soft; // soft constraints
vector<rational> m_weights; // weights of soft constraints
rational m_penalty; // current penalty of soft constraints
rational m_best_penalty;
vector<unsigned_vector> m_hard_occ, m_soft_occ; // variable occurrence
svector<bool> m_assignment; // current assignment.
svector<bool> m_best_assignment;
obj_map<func_decl, unsigned> m_decl2var; // map declarations to Boolean variables.
ptr_vector<func_decl> m_var2decl; // reverse map
uint_set m_hard_false; // list of hard clauses that are false.
uint_set m_soft_false; // list of soft clauses that are false.
unsigned m_max_flips;
uint_set m_hard_false; // list of hard clauses that are false.
uint_set m_soft_false; // list of soft clauses that are false.
unsigned m_max_flips; // maximal number of flips
unsigned m_non_greedy_perc; // percent of moves to do non-greedy style
random_gen m_rng;
imp(ast_manager& m):
m(m),
pb(m),
m_cancel(false)
{
m_max_flips = 100;
m_non_greedy_perc = 30;
}
~imp() {
@ -97,10 +103,16 @@ namespace smt {
}
}
void set_value(func_decl* f, bool b) {
literal lit = mk_literal(f);
SASSERT(!lit.sign());
m_assignment[lit.var()] = b;
void set_model(model const& mdl) {
unsigned sz = mdl.get_num_constants();
for (unsigned i = 0; i < sz; ++i) {
func_decl* f = mdl.get_constant(i);
if (m.is_bool(f->get_range())) {
literal lit = mk_literal(f);
SASSERT(!lit.sign());
m_assignment[lit.var()] = m.is_true(mdl.get_const_interp(f));
}
}
}
lbool operator()() {
@ -110,8 +122,14 @@ namespace smt {
if (m_cancel) {
return l_undef;
}
IF_VERBOSE(3, verbose_stream()
<< "(pb.sls violated: " << m_hard_false.num_elems()
<< " penalty: " << m_penalty << ")\n";);
if (m_best_penalty.is_zero()) {
return l_true;
}
}
return l_undef;
return m_best_assignment.empty()?l_false:l_true;
}
bool get_value(literal l) {
@ -120,11 +138,16 @@ namespace smt {
void set_cancel(bool f) {
m_cancel = f;
}
void get_model(model_ref& mdl) {
mdl = alloc(model, m);
for (unsigned i = 0; i < m_var2decl.size(); ++i) {
mdl->register_decl(m_var2decl[i], m_best_assignment[i]?m.mk_true():m.mk_false());
}
}
void collect_statistics(statistics& st) const {
}
void get_model(model_ref& mdl) {
NOT_IMPLEMENTED_YET();
}
void updt_params(params_ref& p) {
}
@ -155,22 +178,31 @@ namespace smt {
}
void init() {
m_best_assignment.reset();
m_best_penalty.reset();
m_hard_false.reset();
m_hard_occ.reset();
m_soft_false.reset();
m_soft_occ.reset();
m_penalty.reset();
// initialize the occurs vectors.
init_occ(m_clauses, m_hard_occ);
init_occ(m_soft, m_soft_occ);
// add clauses that are false.
for (unsigned i = 0; i < m_clauses.size(); ++i) {
if (!eval(m_clauses[i])) {
m_hard_false.insert(i);
}
}
m_penalty.reset();
for (unsigned i = 0; i < m_soft.size(); ++i) {
if (!eval(m_soft[i])) {
m_soft_false.insert(i);
m_penalty += m_weights[i];
}
}
m_best_penalty = m_penalty;
}
void flip() {
@ -200,8 +232,12 @@ namespace smt {
}
VERIFY(-break_count == flip(~lit));
}
// just do a greedy move:
flip(cls.m_lits[min_bc_index]);
if (m_rng(100) <= m_non_greedy_perc) {
flip(cls.m_lits[m_rng(cls.m_lits.size())]);
}
else {
flip(cls.m_lits[min_bc_index]);
}
}
void flip_soft() {
@ -216,19 +252,30 @@ namespace smt {
break_count = flip(lit);
SASSERT(break_count >= 0);
if (break_count == 0 && penalty > m_penalty) {
// TODO: save into best so far if this qualifies.
if (m_best_penalty > m_penalty) {
IF_VERBOSE(1, verbose_stream() << "(pb.sls improved bound "
<< m_penalty << ")\n";);
m_best_assignment.reset();
m_best_assignment.append(m_assignment);
m_best_penalty = m_penalty;
}
return;
}
if ((break_count < min_bc) ||
(break_count == min_bc && m_penalty < min_penalty)) {
min_bc = break_count;
min_bc_index = i;
min_penality = m_penalty;
min_penalty = m_penalty;
}
VERIFY(-break_count == flip(~lit));
}
// just do a greedy move:
flip(cls.m_lits[min_bc_index]);
if (m_rng(100) <= m_non_greedy_perc) {
flip(cls.m_lits[m_rng(cls.m_lits.size())]);
}
else {
// just do a greedy move:
flip(cls.m_lits[min_bc_index]);
}
}
//
@ -310,13 +357,14 @@ namespace smt {
literal mk_literal(func_decl* f) {
SASSERT(f->get_family_id() == null_family_id);
unsigned var;
if (!m_expr2var.find(f, var)) {
if (!m_decl2var.find(f, var)) {
var = m_hard_occ.size();
SASSERT(m_expr2var.size() == var);
SASSERT(m_var2decl.size() == var);
SASSERT(m_soft_occ.size() == var);
m_hard_occ.push_back(unsigned_vector());
m_soft_occ.push_back(unsigned_vector());
m_assignment.push_back(false);
m_expr2var.insert(f, var);
m_decl2var.insert(f, var);
m_var2decl.push_back(f);
}
return literal(var);
@ -412,8 +460,8 @@ namespace smt {
void pb_sls::add(expr* f, rational const& w) {
m_imp->add(f, w);
}
void pb_sls::set_value(func_decl* f, bool b) {
m_imp->set_value(f, b);
void pb_sls::set_model(model const& mdl) {
m_imp->set_model(mdl);
}
lbool pb_sls::operator()() {
return (*m_imp)();

2
src/opt/pb_sls.h
View file

@ -35,7 +35,7 @@ namespace smt {
~pb_sls();
void add(expr* f);
void add(expr* f, rational const& w);
void set_value(func_decl* f, bool b);
void set_model(model const& mdl);
lbool operator()();
void set_cancel(bool f);
void collect_statistics(statistics& st) const;

11
src/opt/weighted_maxsat.cpp
View file

@ -28,6 +28,7 @@ Notes:
#include "tactical.h"
#include "tactic.h"
#include "model_smt2_pp.h"
#include "pb_sls.h"
namespace smt {
@ -521,6 +522,10 @@ namespace opt {
lbool incremental_solve() {
IF_VERBOSE(3, verbose_stream() << "(incremental solve)\n";);
smt::pb_sls sls(m);
for (unsigned i = 0; i < s.get_num_assertions(); ++i) {
sls.add(s.get_assertion(i));
}
TRACE("opt", tout << "weighted maxsat\n";);
scoped_ensure_theory wth(*this);
solver::scoped_push _s(s);
@ -528,6 +533,7 @@ namespace opt {
bool was_sat = false;
for (unsigned i = 0; i < m_soft.size(); ++i) {
wth().assert_weighted(m_soft[i].get(), m_weights[i]);
sls.add(m_soft[i].get(), m_weights[i]);
}
solver::scoped_push __s(s);
while (l_true == is_sat) {
@ -543,6 +549,11 @@ namespace opt {
model_ref mdl;
s.get_model(mdl);
model_smt2_pp(std::cout, m, *(mdl.get()), 0);
sls.set_model(*(mdl.get()));
lbool found = sls();
std::cout << found << "\n";
}
expr_ref fml = wth().mk_block();
s.assert_expr(fml);