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going over the binary factor for basic lemmas

Signed-off-by: Lev <levnach@hotmail.com>
This commit is contained in:
Lev 2018-09-21 14:26:08 -07:00 committed by Lev Nachmanson
parent 318b505a2e
commit 5344dedf42
10 changed files with 170 additions and 141 deletions

View file

@ -23,7 +23,7 @@ Revision History:
namespace lp {
class column_namer {
public:
virtual std::string get_column_name(unsigned j) const = 0;
virtual std::string get_variable_name(unsigned j) const = 0;
template <typename T>
void print_row(const row_strip<T> & row, std::ostream & out) const {
vector<std::pair<T, unsigned>> coeff;
@ -55,7 +55,7 @@ public:
else if (val != numeric_traits<T>::one())
out << val;
out << get_column_name(it.second);
out << get_variable_name(it.second);
}
}
template <typename T>
@ -78,7 +78,7 @@ public:
else if (val != numeric_traits<T>::one())
out << val;
out << get_column_name(it.second);
out << get_variable_name(it.second);
}
}

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@ -797,7 +797,7 @@ bool int_solver::get_freedom_interval_for_column(unsigned j, bool & inf_l, impq
TRACE("freedom_interval",
tout << "freedom variable for:\n";
tout << m_lar_solver->get_column_name(j);
tout << m_lar_solver->get_variable_name(j);
tout << "[";
if (inf_l) tout << "-oo"; else tout << l;
tout << "; ";

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@ -79,7 +79,7 @@ std::ostream& lar_solver::print_implied_bound(const implied_bound& be, std::ostr
print_term(*m_terms[be.m_j - m_terms_start_index], out);
}
else {
out << get_column_name(v);
out << get_variable_name(v);
}
out << " " << lconstraint_kind_string(be.kind()) << " " << be.m_bound << std::endl;
out << "end of implied bound" << std::endl;
@ -999,15 +999,6 @@ column_type lar_solver::get_column_type(unsigned j) const{
return m_mpq_lar_core_solver.m_column_types[j];
}
std::string lar_solver::get_column_name(unsigned j) const {
if (j >= m_terms_start_index)
return std::string("_t") + T_to_string(j);
if (j >= m_var_register.size())
return std::string("_s") + T_to_string(j);
return std::string("v") + T_to_string(m_var_register.local_to_external(j));
}
bool lar_solver::all_constrained_variables_are_registered(const vector<std::pair<mpq, var_index>>& left_side) {
for (auto it : left_side) {
if (! var_is_registered(it.second))
@ -1290,8 +1281,13 @@ void lar_solver::get_model_do_not_care_about_diff_vars(std::unordered_map<var_in
}
std::string lar_solver::get_variable_name(var_index vi) const {
return get_column_name(vi);
std::string lar_solver::get_variable_name(var_index j) const {
if (j >= m_terms_start_index)
return std::string("_t") + T_to_string(j);
if (j >= m_var_register.size())
return std::string("_s") + T_to_string(j);
return std::string("v") + T_to_string(m_var_register.local_to_external(j));
}
// ********** print region start
@ -1344,7 +1340,7 @@ std::ostream& lar_solver::print_term(lar_term const& term, std::ostream & out) c
out << " - ";
else if (val != numeric_traits<mpq>::one())
out << T_to_string(val);
out << this->get_column_name(p.var());
out << this->get_variable_name(p.var());
}
return out;
}

View file

@ -438,8 +438,6 @@ public:
column_type get_column_type(unsigned j) const;
std::string get_column_name(unsigned j) const override;
bool all_constrained_variables_are_registered(const vector<std::pair<mpq, var_index>>& left_side);
constraint_index add_constraint(const vector<std::pair<mpq, var_index>>& left_side_with_terms, lconstraint_kind kind_par, const mpq& right_side_parm);

View file

@ -780,7 +780,7 @@ copy_rs_to_xB(vector<X> & rs) {
template <typename T, typename X> std::string lp_core_solver_base<T, X>::
column_name(unsigned column) const {
return m_column_names.get_column_name(column);
return m_column_names.get_variable_name(column);
}
template <typename T, typename X> void lp_core_solver_base<T, X>::

View file

@ -96,7 +96,7 @@ public:
void set_cost_for_column(unsigned column, T column_cost) {
get_or_create_column_info(column)->set_cost(column_cost);
}
std::string get_column_name(unsigned j) const override;
std::string get_variable_name(unsigned j) const override;
void set_row_column_coefficient(unsigned row, unsigned column, T const & val) {
m_A_values[row][column] = val;

View file

@ -28,7 +28,7 @@ template <typename T, typename X> column_info<T> * lp_solver<T, X>::get_or_creat
}
template <typename T, typename X>
std::string lp_solver<T, X>::get_column_name(unsigned j) const { // j here is the core solver index
std::string lp_solver<T, X>::get_variable_name(unsigned j) const { // j here is the core solver index
auto it = this->m_core_solver_columns_to_external_columns.find(j);
if (it == this->m_core_solver_columns_to_external_columns.end())
return std::string("x")+T_to_string(j);

View file

@ -6,18 +6,20 @@
#include "util/vector.h"
#include "util/lp/lar_solver.h"
namespace nra {
struct mon_eq {
mon_eq(lp::var_index v, unsigned sz, lp::var_index const* vs):
m_v(v), m_vs(sz, vs) {}
mon_eq(lp::var_index v, const svector<lp::var_index> &vs):
m_v(v), m_vs(vs) {}
lp::var_index m_v;
svector<lp::var_index> m_vs;
unsigned var() const { return m_v; }
unsigned size() const { return m_vs.size(); }
svector<lp::var_index>::const_iterator begin() const { return m_vs.begin(); }
svector<lp::var_index>::const_iterator end() const { return m_vs.end(); }
};
struct mon_eq {
// fields
lp::var_index m_v;
svector<lp::var_index> m_vs;
// constructors
mon_eq(lp::var_index v, unsigned sz, lp::var_index const* vs):
m_v(v), m_vs(sz, vs) {}
mon_eq(lp::var_index v, const svector<lp::var_index> &vs):
m_v(v), m_vs(vs) {}
unsigned var() const { return m_v; }
unsigned size() const { return m_vs.size(); }
svector<lp::var_index>::const_iterator begin() const { return m_vs.begin(); }
svector<lp::var_index>::const_iterator end() const { return m_vs.end(); }
};
typedef std::unordered_map<lp::var_index, rational> variable_map_type;

View file

@ -193,9 +193,9 @@ struct solver::imp {
vars_equivalence m_vars_equivalence;
vector<mon_eq> m_monomials;
// maps the vector of the minimized monomial vars to the list of monomial indices having the same vector
// maps the vector of the minimized monomial vars to the list of the indices of monomials having the same minimized monomial
std::unordered_map<svector<lpvar>, vector<mono_index_with_sign>, hash_svector>
m_minimal_monomials;
m_minimal_monomials;
unsigned_vector m_monomials_lim;
lp::lar_solver& m_lar_solver;
std::unordered_map<lpvar, unsigned_vector> m_var_lists;
@ -252,8 +252,8 @@ struct solver::imp {
if (mon_vars == other_vars_copy &&
values_are_different(m_monomials[i_mon].var(), sign * other_sign, other_m.var())) {
fill_explanation_and_lemma_sign(m_monomials[i_mon],
other_m,
sign * other_sign);
other_m,
sign * other_sign);
TRACE("nla_solver", tout << "lemma generated\n";);
return true;
}
@ -271,9 +271,9 @@ struct solver::imp {
}
std::ostream& print_monomial(const mon_eq& m, std::ostream& out) const {
out << m_lar_solver.get_column_name(m.var()) << " = ";
out << m_lar_solver.get_variable_name(m.var()) << " = ";
for (unsigned k = 0; k < m.size(); k++) {
out << m_lar_solver.get_column_name(m.m_vs[k]);
out << m_lar_solver.get_variable_name(m.m_vs[k]);
if (k + 1 < m.m_vs.size()) out << "*";
}
return out;
@ -328,7 +328,7 @@ struct solver::imp {
// Replaces each variable index by a smaller index and flips the sing if the var comes with a minus.
//
svector<lpvar> reduce_monomial_to_minimal(const svector<lpvar> & vars, int & sign) {
svector<lpvar> reduce_monomial_to_minimal(const svector<lpvar> & vars, int & sign) const {
svector<lpvar> ret;
sign = 1;
for (unsigned i = 0; i < vars.size(); i++) {
@ -341,7 +341,7 @@ struct solver::imp {
/**
* \brief <generate lemma by using the fact that -ab = (-a)b) and
-ab = a(-b)
*/
*/
bool generate_basic_lemma_for_mon_sign(unsigned i_mon) {
if (m_vars_equivalence.empty()) {
return false;
@ -447,7 +447,7 @@ struct solver::imp {
v1 * v2 > 0
c) (v1 < 0 and v2 > 0) or (v1 > 0 and v2 < 0) iff
v1 * v2 < 0
*/
*/
bool generate_basic_lemma_for_mon_zero(unsigned i_mon) {
m_expl->clear();
const auto mon = m_monomials[i_mon];
@ -543,7 +543,7 @@ struct solver::imp {
}
}
if (!monomial)
out << m_lar_solver.get_column_name(j) << " = " << m_lar_solver.get_column_value(j);
out << m_lar_solver.get_variable_name(j) << " = " << m_lar_solver.get_column_value(j);
out <<";";
return out;
}
@ -572,7 +572,7 @@ struct solver::imp {
print_lemma(*m_lemma, out);
out << "\n";
return out;
}
}
/**
* \brief <return true if j is fixed to 1 or -1, and put the value into "sign">
*/
@ -656,7 +656,7 @@ struct solver::imp {
return false;
}
if (m_minimal_monomials.empty() && m.size() > 2)
create_min_map();
create_min_mon_map();
return process_ones_of_mon(m, ones_of_mon, vars, v);
}
@ -674,8 +674,7 @@ struct solver::imp {
}
// returns the variable m_i, of a monomial if found and sets the sign,
// if the
bool find_monomial_of_vars(const svector<lpvar>& vars, unsigned &j, int & sign) {
bool find_monomial_of_vars(const svector<lpvar>& vars, unsigned &j, int & sign) const {
if (vars.size() == 1) {
j = vars[0];
sign = 1;
@ -956,7 +955,7 @@ struct solver::imp {
return false; // we exhausted the mask and did not find the compliment monomial
}
// we derive a lemma from |x| >= 1 => |xy| >= |y| or |x| <= 1 => |xy| <= |y|
// we derive a lemma from |x| >= 1 => |xy| >= |y| or |x| <= 1 => |xy| <= |y|
bool basic_lemma_for_mon_proportionality_from_factors_to_product(unsigned i_mon) {
const mon_eq & m = m_monomials[i_mon];
unsigned_vector large;
@ -967,7 +966,7 @@ struct solver::imp {
return false;
if (m_minimal_monomials.empty())
create_min_map();
create_min_mon_map();
if (!large.empty() && large_basic_lemma_for_mon_proportionality(i_mon, large))
return true;
@ -978,6 +977,10 @@ struct solver::imp {
return false;
}
// Using the following theorems
// |ab| >= |b| iff |a| >= 1 or b = 0
// |ab| <= |b| iff |a| <= 1 or b = 0
// and their commutative variants
bool generate_basic_lemma_for_mon_proportionality(unsigned i_mon) {
TRACE("nla_solver", tout << "generate_basic_lemma_for_mon_proportionality";);
if (basic_lemma_for_mon_proportionality_from_factors_to_product(i_mon))
@ -986,21 +989,35 @@ struct solver::imp {
return basic_lemma_for_mon_proportionality_from_product_to_factors(i_mon);
}
struct signed_two_factorization {
unsigned m_i; // monomial index
struct signed_binary_factorization {
unsigned m_k; // monomial index
int m_sign; //
bool m_k_is_var;
unsigned m_j; // monomial index
bool m_j_is_var;
int m_sign;
// the default constructor
signed_binary_factorization() :m_k(-1) {}
signed_binary_factorization(unsigned k, bool k_is_var, unsigned j, bool j_is_var, int sign) : m_k(k),
m_k_is_var(k_is_var),
m_j(j),
m_j_is_var(j_is_var),
m_sign(sign) {}
bool k_is_var() const { return m_k_is_var; }
bool j_is_var() const { return m_j_is_var; }
};
struct factors_of_monomial {
struct binary_factorizations_of_monomial {
unsigned m_i_mon;
const imp& m_imp;
const mon_eq& m_mon;
unsigned_vector m_minimized_vars;
int m_sign;
factors_of_monomial(unsigned i_mon, const imp& s) : m_i_mon(i_mon), m_imp(s),
int m_sign; // the sign appears after reducing the monomial "mm_mon" to the minimal one
binary_factorizations_of_monomial(unsigned i_mon, const imp& s) : m_i_mon(i_mon), m_imp(s),
m_mon(m_imp.m_monomials[i_mon]) {
// m_minimized_vars = reduce_monomial_to_minimal(i_mon, m_sign);
m_minimized_vars = m_imp.reduce_monomial_to_minimal(
m_imp.m_monomials[m_i_mon].m_vs, m_sign);
}
@ -1008,79 +1025,77 @@ struct solver::imp {
struct const_iterator {
// fields
unsigned_vector m_mask;
// factors_of_monomial& m_fm;
const binary_factorizations_of_monomial& m_binary_factorizations;
//typedefs
typedef const_iterator self_type;
typedef signed_two_factorization value_type;
typedef const signed_two_factorization reference;
// typedef const column_cell* pointer;
typedef signed_binary_factorization value_type;
typedef const signed_binary_factorization reference;
typedef int difference_type;
typedef std::forward_iterator_tag iterator_category;
bool get_factors(unsigned& k, unsigned& j) {
/*
unsigned_vector a;
unsigned_vector b;
void init_vars_by_the_mask(unsigned_vector & k_vars, unsigned_vector & j_vars) const {
for (unsigned j = 0; j < m_mask.size(); j++) {
if (m_mask[j] == 1) {
a.push_back(m_fm.m_minimized_vars[j]);
k_vars.push_back(m_binary_factorizations.m_minimized_vars[j]);
} else {
b.push_back(m_fm.m_minimized_vars[j]);
j_vars.push_back(m_binary_factorizations.m_minimized_vars[j]);
}
}
SASSERT(!a.empty() && !b.empty());
std::sort(a.begin(), a.end());
std::sort(b.begin(), b.end());
int a_sign, b_sign;
if (a.size() == 1) {
k = a[0];
a_sign = 1;
} else if (!m_imp.find_monomial_of_vars(a, k, a_sign)) {
return false;
}
bool get_factors(unsigned& k, bool& k_is_var, unsigned& j, bool& j_is_var, int& sign) const {
unsigned_vector k_vars;
unsigned_vector j_vars;
init_vars_by_the_mask(k_vars, j_vars);
SASSERT(!k_vars.empty() && !j_vars.empty());
std::sort(k_vars.begin(), k_vars.end());
std::sort(j_vars.begin(), j_vars.end());
int k_sign, j_sign;
if (k_vars.size() == 1) {
k = k_vars[0];
k_sign = 1;
k_is_var = true;
} else if (m_binary_factorizations.m_imp.find_monomial_of_vars(k_vars, k, k_sign)) {
k_is_var = false;
} else {
return false;
}
if (b.size() == 1) {
j = b[0];
b_sign = 1;
} else if (!m_imp.find_monomial_of_vars(b, j, b_sign)) {
return false;
} else {
return false;
}
*/
SASSERT(false); // not implemented
return false;
if (j_vars.size() == 1) {
j = j_vars[0];
j_sign = 1;
j_is_var = true;
} else if (m_binary_factorizations.m_imp.find_monomial_of_vars(j_vars, j, j_sign)) {
j_is_var = false;
} else return false;
sign = j_sign * k_sign;
return true;
}
reference operator*() const {
SASSERT(false); // not implemented
// unsigned k, j; // the factors
//if (!get_factors(k, j))
// return std::pair<lpvar, lpvar>(static_cast<unsigned>(-1), 0);
return signed_two_factorization();
// return std::pair<lpvar, lpvar>(k, j);
unsigned k,j; int sign;
bool k_is_var, j_is_var;
if (!get_factors(k, k_is_var, j, j_is_var, sign))
return signed_binary_factorization();
return signed_binary_factorization(k, k_is_var, j, j_is_var, m_binary_factorizations.m_sign * sign);
}
void advance_mask() {
SASSERT(false);// not implemented
/*
for (unsigned k = 0; k < m_masl.size(); k++) {
if (mask[k] == 0){
mask[k] = 1;
break;
} else {
mask[k] = 0;
}
}*/
for (unsigned k = 0; k < m_masl.size(); k++) {
if (mask[k] == 0){
mask[k] = 1;
break;
} else {
mask[k] = 0;
}
}*/
}
self_type operator++() { self_type i = *this; operator++(1); return i; }
self_type operator++(int) { advance_mask(); return *this; }
const_iterator(const unsigned_vector& mask) :
m_mask(mask) {
const_iterator(const unsigned_vector& mask, const binary_factorizations_of_monomial & f) : m_mask(mask), m_binary_factorizations(f) {
// SASSERT(false);
}
bool operator==(const self_type &other) const {
@ -1092,23 +1107,39 @@ struct solver::imp {
const_iterator begin() const {
unsigned_vector mask(m_mon.m_vs.size(), static_cast<lpvar>(0));
mask[0] = 1;
return const_iterator(mask);
return const_iterator(mask, *this);
}
const_iterator end() const {
unsigned_vector mask(m_mon.m_vs.size(), 1);
return const_iterator(mask);
return const_iterator(mask, *this);
}
};
bool lemma_for_proportional_factors(unsigned i_mon, lpvar a, lpvar b) {
return false;
bool lemma_for_proportional_factors(unsigned i_mon, const signed_binary_factorization& f) {
TRACE("nla_solver", print_monomial(m_monomials[i_mon], tout);
tout << " is factorized as ";
if (f.m_sign == -1) { tout << "-";}
if (f.k_is_var()) {
tout << m_lar_solver.get_variable_name(f.m_k);
} else {
print_monomial(m_monomials[f.m_k], tout);
}
tout << "*";
if (f.j_is_var()) {
tout << m_lar_solver.get_variable_name(f.m_j);
} else {
print_monomial(m_monomials[f.m_j], tout);
});
SASSERT(false);
return false; // not implemented
}
// we derive a lemma from |xy| > |y| => |x| >= 1 || |y| = 0
// we derive a lemma from |xy| >= |y| => |x| >= 1 || |y| = 0
bool basic_lemma_for_mon_proportionality_from_product_to_factors(unsigned i_mon) {
for (auto factors : factors_of_monomial(i_mon, *this)) {
// if (lemma_for_proportional_factors(i_mon, factors.first, factors.second))
for (auto factorization : binary_factorizations_of_monomial(i_mon, *this)) {
if (lemma_for_proportional_factors(i_mon, factorization))
return true;
}
// return true;
// return true;
SASSERT(false);
return false;
}
@ -1132,7 +1163,7 @@ struct solver::imp {
return false;
}
void map_monomials_var_to_monomial_indices(unsigned i) {
void map_monomial_vars_to_monomial_indices(unsigned i) {
const mon_eq& m = m_monomials[i];
for (lpvar j : m.m_vs) {
auto it = m_var_lists.find(j);
@ -1149,35 +1180,37 @@ struct solver::imp {
void map_vars_to_monomials_and_constraints() {
for (unsigned i = 0; i < m_monomials.size(); i++)
map_monomials_var_to_monomial_indices(i);
map_monomial_vars_to_monomial_indices(i);
}
// x is equivalent to y if x = +- y
void init_vars_equivalence() {
m_vars_equivalence.init(m_lar_solver);
}
void add_pair_to_min_monomials(const svector<lpvar>& key, unsigned i, int sign) {
void register_key_mono_in_min_monomials(const svector<lpvar>& key, unsigned i, int sign) {
mono_index_with_sign ms(i, sign);
auto it = m_minimal_monomials.find(key);
if (it == m_minimal_monomials.end()) {
vector<mono_index_with_sign> v;
v.push_back(ms);
// v is a vector containing a single mono_index_with_sign
m_minimal_monomials.emplace(key, v);
} else {
it->second.push_back(ms);
}
}
void add_monomial_to_min_map(unsigned i) {
void register_monomial_in_min_map(unsigned i) {
const mon_eq& m = m_monomials[i];
int sign;
svector<lpvar> key = reduce_monomial_to_minimal(m.m_vs, sign);
add_pair_to_min_monomials(key, i, sign);
register_key_mono_in_min_monomials(key, i, sign);
}
void create_min_map() {
void create_min_mon_map() {
for (unsigned i = 0; i < m_monomials.size(); i++)
add_monomial_to_min_map(i);
register_monomial_in_min_map(i);
}
void init_search() {
@ -1225,30 +1258,30 @@ lbool solver::check(lp::explanation & ex, lemma& l) {
}; // end of imp
void solver::add_monomial(lpvar v, unsigned sz, lpvar const* vs) {
m_imp->add(v, sz, vs);
}
void solver::add_monomial(lpvar v, unsigned sz, lpvar const* vs) {
m_imp->add(v, sz, vs);
}
bool solver::need_check() { return true; }
bool solver::need_check() { return true; }
lbool solver::check(lp::explanation & ex, lemma& l) {
return m_imp->check(ex, l);
}
lbool solver::check(lp::explanation & ex, lemma& l) {
return m_imp->check(ex, l);
}
void solver::push(){
m_imp->push();
}
void solver::push(){
m_imp->push();
}
void solver::pop(unsigned n) {
m_imp->pop(n);
}
void solver::pop(unsigned n) {
m_imp->pop(n);
}
solver::solver(lp::lar_solver& s, reslimit& lim, params_ref const& p) {
m_imp = alloc(imp, s, lim, p);
}
solver::solver(lp::lar_solver& s, reslimit& lim, params_ref const& p) {
m_imp = alloc(imp, s, lim, p);
}
solver::~solver() {
dealloc(m_imp);
}
solver::~solver() {
dealloc(m_imp);
}
}