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working on core-maxsat

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2013-11-09 15:54:38 -08:00
parent 2349a0fcdd
commit 293a97bdfc
7 changed files with 52 additions and 22 deletions

30
src/opt/core_maxsat.cpp
View file

@ -18,6 +18,7 @@ Notes:
--*/
#include "core_maxsat.h"
#include "card_decl_plugin.h"
#include "ast_pp.h"
namespace opt {
@ -36,9 +37,9 @@ namespace opt {
solver::scoped_push _sp(s);
for (unsigned i = 0; i < m_soft.size(); ++i) {
expr* a = m.mk_fresh_const("p", m.mk_bool_sort());
aux.push_back(a);
s.assert_expr(m.mk_implies(a, m_soft[i].get()));
block_vars.insert(a);
aux.push_back(m.mk_not(a));
s.assert_expr(m.mk_or(a, m_soft[i].get()));
block_vars.insert(aux.back());
}
while (m_answer.size() < m_upper) {
ptr_vector<expr> vars;
@ -60,20 +61,30 @@ namespace opt {
ans.push_back(m_soft[i].get());
}
}
TRACE("opt", tout << "sat\n";
for (unsigned i = 0; i < ans.size(); ++i) {
tout << mk_pp(ans[i].get(), m) << "\n";
});
if (ans.size() > m_answer.size()) {
m_answer.reset();
m_answer.append(ans);
}
unsigned k = m_soft.size()-m_answer.size()-1; // TBD: fix this
unsigned k = m_soft.size()-m_answer.size()-1;
expr_ref fml = mk_at_most(core_vars, k);
TRACE("opt", tout << "add: " << fml << "\n";);
s.assert_expr(fml);
break;
}
case l_false: {
ptr_vector<expr> core;
s.get_unsat_core(core);
TRACE("opt", tout << "core";
for (unsigned i = 0; i < core.size(); ++i) {
tout << mk_pp(core[i], m) << " ";
}
tout << "\n";);
for (unsigned i = 0; i < core.size(); ++i) {
core_vars.insert(core[i]);
core_vars.insert(get_not(core[i]));
block_vars.remove(core[i]);
}
if (core.empty()) {
@ -84,9 +95,10 @@ namespace opt {
// at least one core variable is True
expr_ref fml = mk_at_most(core_vars, 0);
fml = m.mk_not(fml);
TRACE("opt", tout << "add: " << fml << "\n";);
s.assert_expr(fml);
}
--m_upper;
--m_upper;
}
}
}
@ -107,6 +119,12 @@ namespace opt {
set2vector(set, es);
return expr_ref(card.mk_at_most_k(es.size(), es.c_ptr(), k), m);
}
expr* core_maxsat::get_not(expr* e) const {
expr* result = 0;
VERIFY(m.is_not(e, result));
return result;
}
rational core_maxsat::get_lower() const {
return rational(m_answer.size());

1
src/opt/core_maxsat.h
View file

@ -44,6 +44,7 @@ namespace opt {
private:
void set2vector(expr_set const& set, ptr_vector<expr>& es) const;
expr_ref mk_at_most(expr_set const& set, unsigned k);
expr* get_not(expr* e) const;
};
};

10
src/opt/fu_malik.h
View file

@ -6,6 +6,7 @@ Module Name:
fu_malik.h
Abstract:
Fu&Malik built-in optimization method.
Adapted from sample code in C.
@ -15,6 +16,10 @@ Author:
Notes:
Takes solver with hard constraints added.
Returns a maximal satisfying subset of soft_constraints
that are still consistent with the solver state.
--*/
#ifndef _OPT_FU_MALIK_H_
#define _OPT_FU_MALIK_H_
@ -23,11 +28,6 @@ Notes:
#include "maxsmt.h"
namespace opt {
/**
Takes solver with hard constraints added.
Returns a maximal satisfying subset of soft_constraints
that are still consistent with the solver state.
*/
class fu_malik : public maxsmt_solver {
struct imp;

13
src/opt/maxsmt.cpp
View file

@ -3,7 +3,7 @@ Copyright (c) 2013 Microsoft Corporation
Module Name:
opt_maxsmt.cpp
maxsmt.cpp
Abstract:
@ -19,8 +19,10 @@ Notes:
#include "maxsmt.h"
#include "fu_malik.h"
#include "core_maxsat.h"
#include "weighted_maxsat.h"
#include "ast_pp.h"
#include "opt_params.hpp"
namespace opt {
@ -35,7 +37,12 @@ namespace opt {
m_answer.append(m_soft_constraints);
}
else if (is_maxsat_problem(m_weights)) {
m_msolver = alloc(fu_malik, m, s, m_soft_constraints);
if (m_maxsat_engine == symbol("core_maxsat")) {
m_msolver = alloc(core_maxsat, m, s, m_soft_constraints);
}
else {
m_msolver = alloc(fu_malik, m, s, m_soft_constraints);
}
}
else {
m_msolver = alloc(wmaxsmt, m, opt_solver::to_opt(s), m_soft_constraints, m_weights);
@ -110,6 +117,8 @@ namespace opt {
}
void maxsmt::updt_params(params_ref& p) {
opt_params _p(p);
m_maxsat_engine = _p.maxsat_engine();
}

3
src/opt/maxsmt.h
View file

@ -3,7 +3,7 @@ Copyright (c) 2013 Microsoft Corporation
Module Name:
opt_maxsmt.h
maxsmt.h
Abstract:
@ -47,6 +47,7 @@ namespace opt {
expr_ref_vector m_answer;
vector<rational> m_weights;
scoped_ptr<maxsmt_solver> m_msolver;
symbol m_maxsat_engine;
public:
maxsmt(ast_manager& m): m(m), m_s(0), m_cancel(false), m_soft_constraints(m), m_answer(m) {}

1
src/opt/opt_params.pyg
View file

@ -3,6 +3,7 @@ def_module_params('opt',
export=True,
params=(('timeout', UINT, UINT_MAX, 'set timeout'),
('engine', SYMBOL, 'basic', "select optimization engine: 'basic', 'farkas', 'symba'"),
('maxsat_engine', SYMBOL, 'fu_malik', "select engine for non-weighted maxsat: 'fu_malik', 'core_maxsat'"),
('pareto', BOOL, False, 'return a Pareto front (as opposed to a bounding box)'),
))

16
src/smt/theory_card.cpp
View file

@ -453,19 +453,19 @@ namespace smt {
void theory_card::pop_scope_eh(unsigned num_scopes) {
unsigned sz = m_watch_lim[m_watch_lim.size()-num_scopes];
for (unsigned i = m_watch_trail.size(); i > sz; ) {
--i;
while (m_watch_trail.size() > sz) {
ptr_vector<card>* cards = 0;
VERIFY(m_watch.find(m_watch_trail[i], cards));
VERIFY(m_watch.find(m_watch_trail.back(), cards));
SASSERT(cards && !cards->empty());
cards->pop_back();
m_watch_trail.pop_back();
}
m_watch_lim.resize(m_watch_lim.size()-num_scopes);
sz = m_cards_lim[m_cards_lim.size()-num_scopes];
for (unsigned i = m_cards_trail.size(); i > sz; ) {
--i;
SASSERT(m_cards.contains(m_cards_trail[i]));
m_cards.remove(m_cards_trail[i]);
while (m_cards_trail.size() > sz) {
SASSERT(m_cards.contains(m_cards_trail.back()));
m_cards.remove(m_cards_trail.back());
m_cards_trail.pop_back();
}
m_cards_lim.resize(m_cards_lim.size()-num_scopes);
}
@ -482,7 +482,7 @@ namespace smt {
TRACE("card", ctx.display_literals_verbose(tout, lits.size(), lits.c_ptr()); tout << "\n";);
justification* js = 0;
ctx.mk_clause(lits.size(), lits.c_ptr(), js, CLS_AUX_LEMMA, 0);
IF_VERBOSE(0,
IF_VERBOSE(1,
for (unsigned i = 0; i < lits.size(); ++i) {
verbose_stream() << lits[i] << " ";
}