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review of NB

Signed-off-by: Lev Nachmanson <levnach@hotmail.com>
This commit is contained in:
Lev Nachmanson 2019-12-11 16:02:05 -10:00
parent 0db79b1c79
commit d0f682b239
7 changed files with 223 additions and 259 deletions

View file

@ -20,8 +20,9 @@
#include "math/lp/nla_grobner.h"
#include "math/lp/nla_core.h"
#include "math/lp/factorization_factory_imp.h"
namespace nla {
nla_grobner::nla_grobner(core *c, intervals *s)
using namespace nla;
grobner::grobner(core *c, intervals *s)
: common(c, s),
m_nl_gb_exhausted(false),
m_dep_manager(m_val_manager, m_alloc),
@ -29,12 +30,30 @@ nla_grobner::nla_grobner(core *c, intervals *s)
m_look_for_fixed_vars_in_rows(false)
{}
bool nla_grobner::internalize_gb_eq(equation* ) {
void grobner::grobner_lemmas() {
c().lp_settings().stats().m_grobner_calls++;
init();
ptr_vector<equation> eqs;
unsigned next_weight =
(unsigned)(var_weight::MAX_DEFAULT_WEIGHT) + 1; // next weight using during perturbation phase.
do {
TRACE("grobner", tout << "before:\n"; display(tout););
compute_basis();
update_statistics();
TRACE("grobner", tout << "after:\n"; display(tout););
// if (find_conflict(eqs))
// return;
} while (push_calculation_forward(eqs, next_weight));
}
bool grobner::internalize_gb_eq(equation* ) {
NOT_IMPLEMENTED_YET();
return false;
}
void nla_grobner::add_var_and_its_factors_to_q_and_collect_new_rows(lpvar j, std::queue<lpvar> & q) {
void grobner::add_var_and_its_factors_to_q_and_collect_new_rows(lpvar j, std::queue<lpvar> & q) {
SASSERT(!c().active_var_set_contains(j) && !c().var_is_fixed(j));
TRACE("grobner", tout << "j = " << j << ", "; c().print_var(j, tout) << "\n";);
const auto& matrix = c().m_lar_solver.A_r();
@ -69,7 +88,7 @@ void nla_grobner::add_var_and_its_factors_to_q_and_collect_new_rows(lpvar j, std
}
}
void nla_grobner::find_nl_cluster() {
void grobner::find_nl_cluster() {
prepare_rows_and_active_vars();
std::queue<lpvar> q;
for (lpvar j : c().m_to_refine) {
@ -92,13 +111,13 @@ void nla_grobner::find_nl_cluster() {
TRACE("grobner", display(tout););
}
void nla_grobner::prepare_rows_and_active_vars() {
void grobner::prepare_rows_and_active_vars() {
m_rows.clear();
m_rows.resize(c().m_lar_solver.row_count());
c().clear_and_resize_active_var_set();
}
void nla_grobner::display_matrix(std::ostream & out) const {
void grobner::display_matrix(std::ostream & out) const {
const auto& matrix = c().m_lar_solver.A_r();
out << m_rows.size() << " rows" <<"\n";
out << "the matrix\n";
@ -107,21 +126,21 @@ void nla_grobner::display_matrix(std::ostream & out) const {
c().print_term(r, out) << std::endl;
}
}
std::ostream & nla_grobner::display(std::ostream & out) const {
std::ostream & grobner::display(std::ostream & out) const {
display_equations(out, m_to_superpose, "m_to_superpose:");
display_equations(out, m_to_simplify, "m_to_simplify:");
return out;
}
common::ci_dependency* nla_grobner::dep_from_vector(svector<lp::constraint_index> & cs) {
common::ci_dependency* grobner::dep_from_vector(svector<lp::constraint_index> & cs) {
ci_dependency * d = nullptr;
for (auto c : cs)
d = m_dep_manager.mk_join(d, m_dep_manager.mk_leaf(c));
return d;
}
void nla_grobner::add_row(unsigned i) {
void grobner::add_row(unsigned i) {
const auto& row = c().m_lar_solver.A_r().m_rows[i];
TRACE("grobner", tout << "adding row to gb\n"; c().m_lar_solver.print_row(row, tout) << '\n';
for (auto p : row) {
@ -135,13 +154,13 @@ void nla_grobner::add_row(unsigned i) {
assert_eq_0(e, dep);
}
void nla_grobner::simplify_equations_in_m_to_simplify() {
void grobner::simplify_equations_in_m_to_simplify() {
for (equation *eq : m_to_simplify) {
eq->expr() = m_nex_creator.simplify(eq->expr());
}
}
void nla_grobner::init() {
void grobner::init() {
m_reported = 0;
del_equations(0);
SASSERT(m_equations_to_delete.size() == 0);
@ -157,13 +176,13 @@ void nla_grobner::init() {
simplify_equations_in_m_to_simplify();
}
bool nla_grobner::is_trivial(equation* eq) const {
SASSERT(m_nex_creator.is_simplified(eq->expr()));
bool grobner::is_trivial(equation* eq) const {
SASSERT(m_nex_creator.is_simplified(*eq->expr()));
return eq->expr()->size() == 0;
}
// returns true if eq1 is simpler than eq2
bool nla_grobner::is_simpler(equation * eq1, equation * eq2) {
bool grobner::is_simpler(equation * eq1, equation * eq2) {
if (!eq2)
return true;
if (is_trivial(eq1))
@ -173,7 +192,7 @@ bool nla_grobner::is_simpler(equation * eq1, equation * eq2) {
return m_nex_creator.gt(eq2->expr(), eq1->expr());
}
void nla_grobner::del_equation(equation * eq) {
void grobner::del_equation(equation * eq) {
m_to_superpose.erase(eq);
m_to_simplify.erase(eq);
SASSERT(m_equations_to_delete[eq->m_bidx] == eq);
@ -181,7 +200,7 @@ void nla_grobner::del_equation(equation * eq) {
dealloc(eq);
}
nla_grobner::equation* nla_grobner::pick_next() {
grobner::equation* grobner::pick_next() {
equation * r = nullptr;
ptr_buffer<equation> to_delete;
for (equation * curr : m_to_simplify) {
@ -200,7 +219,7 @@ nla_grobner::equation* nla_grobner::pick_next() {
return r;
}
nla_grobner::equation* nla_grobner::simplify_using_to_superpose(equation* eq) {
grobner::equation* grobner::simplify_using_to_superpose(equation* eq) {
bool result = false;
bool simplified;
TRACE("grobner", tout << "simplifying: "; display_equation(tout, *eq); tout << "using equalities of m_to_superpose of size " << m_to_superpose.size() << "\n";);
@ -229,7 +248,7 @@ nla_grobner::equation* nla_grobner::simplify_using_to_superpose(equation* eq) {
return result ? eq : nullptr;
}
const nex* nla_grobner::get_highest_monomial(const nex* e) const {
const nex* grobner::get_highest_monomial(const nex* e) const {
switch (e->type()) {
case expr_type::MUL:
return to_mul(e);
@ -245,7 +264,7 @@ const nex* nla_grobner::get_highest_monomial(const nex* e) const {
// source 3f + k + l = 0, so f = (-k - l)/3
// target 2fg + 3fp + e = 0
// target is replaced by 2(-k/3 - l/3)g + 3(-k/3 - l/3)p + e = -2/3kg -2/3lg - kp -lp + e
bool nla_grobner::simplify_target_monomials(equation * source, equation * target) {
bool grobner::simplify_target_monomials(equation * source, equation * target) {
auto * high_mon = get_highest_monomial(source->expr());
if (high_mon == nullptr)
return false;
@ -266,7 +285,7 @@ bool nla_grobner::simplify_target_monomials(equation * source, equation * target
return simplify_target_monomials_sum(source, target, targ_sum, high_mon);
}
unsigned nla_grobner::find_divisible(nex_sum* targ_sum,
unsigned grobner::find_divisible(nex_sum* targ_sum,
const nex* high_mon) const {
for (unsigned j = 0; j < targ_sum->size(); j++) {
auto t = (*targ_sum)[j];
@ -280,7 +299,7 @@ unsigned nla_grobner::find_divisible(nex_sum* targ_sum,
}
bool nla_grobner::simplify_target_monomials_sum(equation * source,
bool grobner::simplify_target_monomials_sum(equation * source,
equation * target, nex_sum* targ_sum,
const nex* high_mon) {
unsigned j = find_divisible(targ_sum, high_mon);
@ -298,16 +317,16 @@ bool nla_grobner::simplify_target_monomials_sum(equation * source,
return true;
}
nex_mul* nla_grobner::divide_ignore_coeffs(nex* ej, const nex* h) {
nex_mul* grobner::divide_ignore_coeffs(nex* ej, const nex* h) {
TRACE("grobner", tout << "ej = " << *ej << " , h = " << *h << "\n";);
if (!divide_ignore_coeffs_check_only(ej, h))
return nullptr;
return divide_ignore_coeffs_perform(ej, h);
}
bool nla_grobner::divide_ignore_coeffs_check_only_nex_mul(nex_mul* t , const nex* h) const {
bool grobner::divide_ignore_coeffs_check_only_nex_mul(nex_mul* t , const nex* h) const {
TRACE("grobner", tout << "t = " << *t << ", h=" << *h << "\n";);
SASSERT(m_nex_creator.is_simplified(t) && m_nex_creator.is_simplified(h));
SASSERT(m_nex_creator.is_simplified(*t) && m_nex_creator.is_simplified(*h));
unsigned j = 0; // points to t
for(unsigned k = 0; k < h->number_of_child_powers(); k++) {
lpvar h_var = to_var(h->get_child_exp(k))->var();
@ -331,7 +350,7 @@ bool nla_grobner::divide_ignore_coeffs_check_only_nex_mul(nex_mul* t , const nex
}
// return true if h divides t
bool nla_grobner::divide_ignore_coeffs_check_only(nex* n , const nex* h) const {
bool grobner::divide_ignore_coeffs_check_only(nex* n , const nex* h) const {
if (n->is_mul())
return divide_ignore_coeffs_check_only_nex_mul(to_mul(n), h);
if (!n->is_var())
@ -354,7 +373,7 @@ bool nla_grobner::divide_ignore_coeffs_check_only(nex* n , const nex* h) const {
return false;
}
nex_mul * nla_grobner::divide_ignore_coeffs_perform_nex_mul(nex_mul* t, const nex* h) {
nex_mul * grobner::divide_ignore_coeffs_perform_nex_mul(nex_mul* t, const nex* h) {
nex_mul * r = m_nex_creator.mk_mul();
unsigned j = 0; // points to t
for(unsigned k = 0; k < h->number_of_child_powers(); k++) {
@ -379,7 +398,7 @@ nex_mul * nla_grobner::divide_ignore_coeffs_perform_nex_mul(nex_mul* t, const ne
// perform the division t / h, but ignores the coefficients
// h does not change
nex_mul * nla_grobner::divide_ignore_coeffs_perform(nex* e, const nex* h) {
nex_mul * grobner::divide_ignore_coeffs_perform(nex* e, const nex* h) {
if (e->is_mul())
return divide_ignore_coeffs_perform_nex_mul(to_mul(e), h);
SASSERT(e->is_var());
@ -390,7 +409,7 @@ nex_mul * nla_grobner::divide_ignore_coeffs_perform(nex* e, const nex* h) {
// and b*high_mon + e = 0, so high_mon = -e/b
// then targ_sum->children()[j] = - (c/b) * e*p
void nla_grobner::simplify_target_monomials_sum_j(equation * source, equation *target, nex_sum* targ_sum, const nex* high_mon, unsigned j) {
void grobner::simplify_target_monomials_sum_j(equation * source, equation *target, nex_sum* targ_sum, const nex* high_mon, unsigned j) {
nex * ej = (*targ_sum)[j];
TRACE("grobner_d", tout << "high_mon = " << *high_mon << ", ej = " << *ej << "\n";);
nex_mul * ej_over_high_mon = divide_ignore_coeffs(ej, high_mon);
@ -409,11 +428,11 @@ void nla_grobner::simplify_target_monomials_sum_j(equation * source, equation *t
}
// return true iff simplified
bool nla_grobner::simplify_source_target(equation * source, equation * target) {
bool grobner::simplify_source_target(equation * source, equation * target) {
TRACE("grobner", tout << "simplifying: "; display_equation(tout, *target); tout << "using: "; display_equation(tout, *source););
TRACE("grobner_d", tout << "simplifying: " << *(target->expr()) << " using " << *(source->expr()) << "\n";);
SASSERT(m_nex_creator.is_simplified(source->expr()));
SASSERT(m_nex_creator.is_simplified(target->expr()));
SASSERT(m_nex_creator.is_simplified(*source->expr()));
SASSERT(m_nex_creator.is_simplified(*target->expr()));
if (target->expr()->is_scalar()) {
TRACE("grobner_d", tout << "no simplification\n";);
return false;
@ -442,7 +461,7 @@ bool nla_grobner::simplify_source_target(equation * source, equation * target) {
return false;
}
void nla_grobner::process_simplified_target(equation* target, ptr_buffer<equation>& to_remove) {
void grobner::process_simplified_target(equation* target, ptr_buffer<equation>& to_remove) {
if (is_trivial(target)) {
to_remove.push_back(target);
} else if (m_changed_leading_term) {
@ -451,7 +470,7 @@ void nla_grobner::process_simplified_target(equation* target, ptr_buffer<equatio
}
}
void nla_grobner::check_eq(equation* target) {
void grobner::check_eq(equation* target) {
if(m_intervals->check_nex(target->expr(), target->dep())) {
TRACE("grobner", tout << "created a lemma for "; display_equation(tout, *target) << "\n";
tout << "vars = \n";
@ -463,7 +482,7 @@ void nla_grobner::check_eq(equation* target) {
}
}
bool nla_grobner::simplify_to_superpose_with_eq(equation* eq) {
bool grobner::simplify_to_superpose_with_eq(equation* eq) {
TRACE("grobner_d", tout << "eq->exp " << *(eq->expr()) << "\n";);
ptr_buffer<equation> to_insert;
@ -481,7 +500,7 @@ bool nla_grobner::simplify_to_superpose_with_eq(equation* eq) {
if (is_trivial(target))
to_delete.push_back(target);
else
SASSERT(m_nex_creator.is_simplified(target->expr()));
SASSERT(m_nex_creator.is_simplified(*target->expr()));
}
for (equation* eq : to_insert)
insert_to_superpose(eq);
@ -495,7 +514,7 @@ bool nla_grobner::simplify_to_superpose_with_eq(equation* eq) {
/*
Use the given equation to simplify m_to_simplify equations
*/
void nla_grobner::simplify_m_to_simplify(equation* eq) {
void grobner::simplify_m_to_simplify(equation* eq) {
TRACE("grobner_d", tout << "eq->exp " << *(eq->expr()) << "\n";);
ptr_buffer<equation> to_delete;
for (equation* target : m_to_simplify) {
@ -509,7 +528,7 @@ void nla_grobner::simplify_m_to_simplify(equation* eq) {
// if e is the sum then add to r all children of e multiplied by beta, except the first one
// which corresponds to the highest monomial,
// otherwise do nothing
void nla_grobner::add_mul_skip_first(nex_sum* r, const rational& beta, nex *e, nex_mul* c) {
void grobner::add_mul_skip_first(nex_sum* r, const rational& beta, nex *e, nex_mul* c) {
if (e->is_sum()) {
nex_sum *es = to_sum(e);
for (unsigned j = 1; j < es->size(); j++) {
@ -523,7 +542,7 @@ void nla_grobner::add_mul_skip_first(nex_sum* r, const rational& beta, nex *e, n
// let e1: alpha*ab+q=0, and e2: beta*ac+e=0, then beta*qc - alpha*eb = 0
nex * nla_grobner::expr_superpose(nex* e1, nex* e2, const nex* ab, const nex* ac, nex_mul* b, nex_mul* c) {
nex * grobner::expr_superpose(nex* e1, nex* e2, const nex* ab, const nex* ac, nex_mul* b, nex_mul* c) {
TRACE("grobner", tout << "e1 = " << *e1 << "\ne2 = " << *e2 <<"\n";);
nex_sum * r = m_nex_creator.mk_sum();
rational alpha = - ab->coeff();
@ -540,7 +559,7 @@ nex * nla_grobner::expr_superpose(nex* e1, nex* e2, const nex* ab, const nex* ac
return ret;
}
// let eq1: ab+q=0, and eq2: ac+e=0, then qc - eb = 0
void nla_grobner::superpose(equation * eq1, equation * eq2) {
void grobner::superpose(equation * eq1, equation * eq2) {
TRACE("grobner", tout << "eq1="; display_equation(tout, *eq1) << "eq2="; display_equation(tout, *eq2););
const nex * ab = get_highest_monomial(eq1->expr());
const nex * ac = get_highest_monomial(eq2->expr());
@ -562,13 +581,13 @@ void nla_grobner::superpose(equation * eq1, equation * eq2) {
}
void nla_grobner::register_report() {
void grobner::register_report() {
m_reported++;
m_conflict = true;
}
// Let a be the greatest common divider of ab and bc,
// then ab/a is stored in b, and ac/a is stored in c
bool nla_grobner::find_b_c(const nex* ab, const nex* ac, nex_mul*& b, nex_mul*& c) {
bool grobner::find_b_c(const nex* ab, const nex* ac, nex_mul*& b, nex_mul*& c) {
if (!find_b_c_check_only(ab, ac))
return false;
b = m_nex_creator.mk_mul(); c = m_nex_creator.mk_mul();
@ -614,10 +633,10 @@ bool nla_grobner::find_b_c(const nex* ab, const nex* ac, nex_mul*& b, nex_mul*&
return true;
}
// Finds out if ab and bc have a non-trivial common divider
bool nla_grobner::find_b_c_check_only(const nex* ab, const nex* ac) const {
bool grobner::find_b_c_check_only(const nex* ab, const nex* ac) const {
if (ab == nullptr || ac == nullptr)
return false;
SASSERT(m_nex_creator.is_simplified(ab) && m_nex_creator.is_simplified(ab));
SASSERT(m_nex_creator.is_simplified(*ab) && m_nex_creator.is_simplified(*ac));
unsigned i = 0, j = 0; // i points to ab, j points to ac
for (;;) {
const nex* m = ab->get_child_exp(i);
@ -641,14 +660,14 @@ bool nla_grobner::find_b_c_check_only(const nex* ab, const nex* ac) const {
}
void nla_grobner::superpose(equation * eq) {
void grobner::superpose(equation * eq) {
for (equation * target : m_to_superpose) {
superpose(eq, target);
}
}
// return true iff cannot pick_next()
bool nla_grobner::compute_basis_step() {
bool grobner::compute_basis_step() {
equation * eq = pick_next();
if (!eq) {
TRACE("grobner", tout << "cannot pick an equation\n";);
@ -671,7 +690,7 @@ bool nla_grobner::compute_basis_step() {
return false;
}
void nla_grobner::compute_basis(){
void grobner::compute_basis(){
compute_basis_init();
if (m_rows.size() < 2) {
TRACE("nla_grobner", tout << "there are only " << m_rows.size() << " rows, exiting compute_basis()\n";);
@ -690,16 +709,16 @@ void nla_grobner::compute_basis(){
}
}
}
void nla_grobner::compute_basis_init(){
void grobner::compute_basis_init(){
c().lp_settings().stats().m_grobner_basis_computatins++;
}
bool nla_grobner::canceled() const {
bool grobner::canceled() const {
return c().lp_settings().get_cancel_flag();
}
bool nla_grobner::done() const {
bool grobner::done() const {
if (
num_of_equations() >= c().m_nla_settings.grobner_eqs_threshold()
||
@ -725,7 +744,7 @@ bool nla_grobner::done() const {
return false;
}
bool nla_grobner::compute_basis_loop(){
bool grobner::compute_basis_loop(){
int i = 0;
while (!done()) {
if (compute_basis_step()) {
@ -738,11 +757,11 @@ bool nla_grobner::compute_basis_loop(){
return false;
}
void nla_grobner::set_gb_exhausted(){
void grobner::set_gb_exhausted(){
m_nl_gb_exhausted = true;
}
void nla_grobner::update_statistics(){
void grobner::update_statistics(){
/* todo : implement
m_stats.m_gb_simplify += gb.m_stats.m_simplify;
m_stats.m_gb_superpose += gb.m_stats.m_superpose;
@ -751,36 +770,17 @@ void nla_grobner::update_statistics(){
}
bool nla_grobner::push_calculation_forward(ptr_vector<equation>& eqs, unsigned & next_weight) {
bool grobner::push_calculation_forward(ptr_vector<equation>& eqs, unsigned & next_weight) {
return (!m_nl_gb_exhausted) &&
try_to_modify_eqs(eqs, next_weight);
}
bool nla_grobner::try_to_modify_eqs(ptr_vector<equation>& eqs, unsigned& next_weight) {
bool grobner::try_to_modify_eqs(ptr_vector<equation>& eqs, unsigned& next_weight) {
// NOT_IMPLEMENTED_YET();
return false;
}
void nla_grobner::grobner_lemmas() {
c().lp_settings().stats().m_grobner_calls++;
init();
ptr_vector<equation> eqs;
unsigned next_weight =
(unsigned)(var_weight::MAX_DEFAULT_WEIGHT) + 1; // next weight using during perturbation phase.
do {
TRACE("grobner", tout << "before:\n"; display(tout););
compute_basis();
update_statistics();
TRACE("grobner", tout << "after:\n"; display(tout););
// if (find_conflict(eqs))
// return;
}
while(push_calculation_forward(eqs, next_weight));
}
void nla_grobner:: del_equations(unsigned old_size) {
void grobner:: del_equations(unsigned old_size) {
TRACE("grobner", );
SASSERT(m_equations_to_delete.size() >= old_size);
equation_vector::iterator it = m_equations_to_delete.begin();
@ -794,18 +794,18 @@ void nla_grobner:: del_equations(unsigned old_size) {
m_equations_to_delete.shrink(old_size);
}
void nla_grobner::display_equations(std::ostream & out, equation_set const & v, char const * header) const {
void grobner::display_equations(std::ostream & out, equation_set const & v, char const * header) const {
out << header << "\n";
for (const equation* e : v)
display_equation(out, *e);
}
std::ostream& nla_grobner::display_equation(std::ostream & out, const equation & eq) const {
std::ostream& grobner::display_equation(std::ostream & out, const equation & eq) const {
out << "expr = " << *eq.expr() << "\n";
display_dependency(out, eq.dep());
return out;
}
std::unordered_set<lpvar> nla_grobner::get_vars_of_expr_with_opening_terms(const nex *e ) {
std::unordered_set<lpvar> grobner::get_vars_of_expr_with_opening_terms(const nex *e ) {
auto ret = get_vars_of_expr(e);
auto & ls = c().m_lar_solver;
do {
@ -827,7 +827,7 @@ std::unordered_set<lpvar> nla_grobner::get_vars_of_expr_with_opening_terms(const
} while (true);
}
void nla_grobner::assert_eq_0(nex* e, ci_dependency * dep) {
void grobner::assert_eq_0(nex* e, ci_dependency * dep) {
if (e == nullptr || is_zero_scalar(e))
return;
m_tmp_var_set.clear();
@ -843,7 +843,7 @@ void nla_grobner::assert_eq_0(nex* e, ci_dependency * dep) {
insert_to_simplify(eq);
}
void nla_grobner::init_equation(equation* eq, nex*e, ci_dependency * dep) {
void grobner::init_equation(equation* eq, nex*e, ci_dependency * dep) {
unsigned bidx = m_equations_to_delete.size();
eq->m_bidx = bidx;
eq->dep() = dep;
@ -852,11 +852,11 @@ void nla_grobner::init_equation(equation* eq, nex*e, ci_dependency * dep) {
SASSERT(m_equations_to_delete[eq->m_bidx] == eq);
}
nla_grobner::~nla_grobner() {
grobner::~grobner() {
del_equations(0);
}
std::ostream& nla_grobner::display_dependency(std::ostream& out, ci_dependency* dep) const {
std::ostream& grobner::display_dependency(std::ostream& out, ci_dependency* dep) const {
svector<lp::constraint_index> expl;
m_dep_manager.linearize(dep, expl);
{
@ -872,5 +872,4 @@ std::ostream& nla_grobner::display_dependency(std::ostream& out, ci_dependency*
return out;
}
} // end of nla namespace