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nla_interval initial review (#101)

* updates

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* code review of nla_intervals: combine functionality

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* tidy

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

* formatting

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2019-12-16 14:02:41 -08:00 committed by Lev Nachmanson
parent 26956cafb0
commit b6c28764f8
2 changed files with 346 additions and 616 deletions

View file

@ -4,34 +4,7 @@
#include "util/mpq.h"
namespace nla {
void intervals::set_var_interval_with_deps(lpvar v, interval& b) const {
TRACE("nla_intervals_details", m_core->print_var(v, tout) << "\n";);
lp::constraint_index ci;
rational val;
bool is_strict;
if (ls().has_lower_bound(v, ci, val, is_strict)) {
m_config.set_lower(b, val);
m_config.set_lower_is_open(b, is_strict);
m_config.set_lower_is_inf(b, false);
b.m_lower_dep = mk_dep(ci);
}
else {
m_config.set_lower_is_open(b, true);
m_config.set_lower_is_inf(b, true);
b.m_lower_dep = nullptr;
}
if (ls().has_upper_bound(v, ci, val, is_strict)) {
m_config.set_upper(b, val);
m_config.set_upper_is_open(b, is_strict);
m_config.set_upper_is_inf(b, false);
b.m_upper_dep = mk_dep(ci);
}
else {
m_config.set_upper_is_open(b, true);
m_config.set_upper_is_inf(b, true);
b.m_upper_dep = nullptr;
}
}
void intervals::set_interval_for_scalar(interv& a, const rational& v) {
set_lower(a, v);
@ -42,105 +15,19 @@ void intervals::set_interval_for_scalar(interv& a, const rational& v) {
set_upper_is_inf(a, false);
}
intervals::interv intervals::power_with_deps(const interv& a, unsigned n) {
interv b;
interval_deps_combine_rule combine_rule;
power(a, n, b, combine_rule);
combine_deps(a, combine_rule, b);
TRACE("nla_horner_details", tout << "power of "; display(tout, a) << " = ";
display(tout, b) << "\n"; );
return b;
}
intervals::interv intervals::interval_of_expr_with_deps(const nex* e, unsigned power) {
interv a;
switch (e->type()) {
case expr_type::SCALAR:
set_interval_for_scalar(a, to_scalar(e)->value());
if (power != 1) {
return power_with_deps(a, power);
}
return a;
case expr_type::SUM:
{
interv b = interval_of_sum_with_deps(to_sum(e));
if (power != 1)
return power_with_deps(b, power);
return b;
}
case expr_type::MUL:
{
interv b = interval_of_mul_with_deps(to_mul(e));
if (power != 1)
return power_with_deps(b, power);;
return b;
}
case expr_type::VAR:
set_var_interval_with_deps(to_var(e)->var(), a);
if (power != 1)
return power_with_deps(a, power);;
return a;
default:
TRACE("nla_intervals_details", tout << e->type() << "\n";);
SASSERT(false);
return interv();
}
}
intervals::interv intervals::interval_of_expr(const nex* e, unsigned power) {
TRACE("nla_intervals_details", tout << "e = " << *e << "\n";);
interv a;
switch (e->type()) {
case expr_type::SCALAR:
set_interval_for_scalar(a, to_scalar(e)->value());
break;
case expr_type::SUM:
{
interv b = interval_of_sum(to_sum(e));
if (power != 1) {
return power_with_deps(b, power);;
}
return b;
}
case expr_type::MUL:
{
interv b = interval_of_mul(to_mul(e));
if (power != 1) {
return power_with_deps(b, power);;
}
return b;
}
case expr_type::VAR:
set_var_interval(to_var(e)->var(), a);
break;
default:
TRACE("nla_intervals_details", tout << e->type() << "\n";);
SASSERT(false);
return interv();
}
if (power != 1) {
return power_with_deps(a, power);;
}
return a;
}
const nex* intervals::get_inf_interval_child(const nex_sum* e) const {
for (auto * c : *e) {
if (has_inf_interval(c))
const nex* intervals::get_inf_interval_child(const nex_sum& e) const {
for (auto * c : e) {
if (has_inf_interval(*c))
return c;
}
return nullptr;
}
bool intervals::mul_has_inf_interval(const nex_mul* e) const {
bool intervals::mul_has_inf_interval(const nex_mul& e) const {
bool has_inf = false;
for (const auto & p : *e) {
const nex *c = p.e();
if (!c->is_elementary())
for (const auto & p : e) {
const nex &c = *p.e();
if (!c.is_elementary())
return false;
if (has_zero_interval(c))
return false;
@ -149,99 +36,33 @@ bool intervals::mul_has_inf_interval(const nex_mul* e) const {
return has_inf;
}
bool intervals::has_inf_interval(const nex* e) const {
if (e->is_var())
return m_core->no_bounds(to_var(e)->var());
if (e->is_mul()) {
return mul_has_inf_interval(to_mul(e));
}
if (e->is_scalar())
bool intervals::has_inf_interval(const nex& e) const {
if (e.is_var())
return m_core->no_bounds(e.to_var().var());
if (e.is_mul())
return mul_has_inf_interval(e.to_mul());
if (e.is_scalar())
return false;
for (auto * c : e->to_sum()) {
if (has_inf_interval(c))
return true;
}
for (auto * c : e.to_sum())
if (has_inf_interval(*c))
return true;
return false;
}
bool intervals::has_zero_interval(const nex* e) const {
SASSERT(!e->is_scalar() || !to_scalar(e)->value().is_zero());
return e->is_var() && m_core->var_is_fixed_to_zero(e->to_var().var());
bool intervals::has_zero_interval(const nex& e) const {
SASSERT(!e.is_scalar() || !e.to_scalar().value().is_zero());
return e.is_var() && m_core->var_is_fixed_to_zero(e.to_var().var());
}
const nex* intervals::get_zero_interval_child(const nex_mul* e) const {
for (const auto & p : *e) {
const nex* intervals::get_zero_interval_child(const nex_mul& e) const {
for (const auto & p : e) {
const nex * c = p.e();
if (has_zero_interval(c))
if (has_zero_interval(*c))
return c;
}
return nullptr;
}
intervals::interv intervals::interval_of_mul_with_deps(const nex_mul* e) {
TRACE("nla_intervals_details", tout << "e = " << *e << "\n";);
const nex * zero_interval_child = get_zero_interval_child(e);
if (zero_interval_child) {
interv a = interval_of_expr_with_deps(zero_interval_child, 1);
set_zero_interval_deps_for_mult(a);
TRACE("nla_intervals_details", tout << "zero_interval_child = "<< *zero_interval_child << std::endl << "a = "; display(tout, a); );
return a;
}
interv a;
set_interval_for_scalar(a, e->coeff());
TRACE("nla_intervals_details", tout << "a = "; display(tout, a); );
for (const auto & ep : *e) {
interv b = interval_of_expr_with_deps(ep.e(), ep.pow());
TRACE("nla_intervals_details", tout << "ep = " << ep << ", "; display(tout, b); );
interv c;
interval_deps_combine_rule comb_rule;
mul_two_intervals(a, b, c, comb_rule);
TRACE("nla_intervals_details", tout << "c before combine_deps() "; display(tout, c););
combine_deps(a, b, comb_rule, c);
TRACE("nla_intervals_details", tout << "a "; display(tout, a););
TRACE("nla_intervals_details", tout << "c "; display(tout, c););
set_with_deps(a, c);
TRACE("nla_intervals_details", tout << "part mult "; display(tout, a););
}
TRACE("nla_intervals_details", tout << "e=" << *e << "\n";
tout << " return "; display(tout, a););
return a;
}
intervals::interv intervals::interval_of_mul(const nex_mul* e) {
TRACE("nla_intervals_details", tout << "e = " << *e << "\n";);
const nex * zero_interval_child = get_zero_interval_child(e);
if (zero_interval_child) {
interv a = interval_of_expr(zero_interval_child, 1);
set_zero_interval_deps_for_mult(a);
TRACE("nla_intervals_details", tout << "zero_interval_child = "<< *zero_interval_child << std::endl << "a = "; display(tout, a); );
return a;
}
interv a;
set_interval_for_scalar(a, e->coeff());
TRACE("nla_intervals_details", tout << "a = "; display(tout, a); );
for (const auto & ep : *e) {
interv b = interval_of_expr(ep.e(), ep.pow() );
TRACE("nla_intervals_details", tout << "ep = " << ep << ", "; display(tout, b); );
interv c;
interval_deps_combine_rule comb_rule;
mul_two_intervals(a, b, c, comb_rule);
TRACE("nla_intervals_details", tout << "c before combine_deps() "; display(tout, c););
combine_deps(a, b, comb_rule, c);
TRACE("nla_intervals_details", tout << "a "; display(tout, a););
TRACE("nla_intervals_details", tout << "c "; display(tout, c););
set_with_no_deps(a, c);
TRACE("nla_intervals_details", tout << "part mult "; display(tout, a););
}
TRACE("nla_intervals_details", tout << "e=" << *e << "\n";
tout << " return "; display(tout, a););
return a;
}
std::ostream & intervals::print_dependencies(ci_dependency* deps , std::ostream& out) const {
svector<lp::constraint_index> expl;
m_dep_manager.linearize(deps, expl);
@ -260,64 +81,18 @@ std::ostream & intervals::print_dependencies(ci_dependency* deps , std::ostream&
// return true iff the interval of n is does not contain 0
bool intervals::check_nex(const nex* n, ci_dependency* initial_deps) {
m_core->lp_settings().stats().m_cross_nested_forms++;
auto i = interval_of_expr(n, 1);
auto i = interval_of_expr<without_deps>(n, 1);
if (!separated_from_zero(i)) {
reset();
return false;
}
auto interv_wd = interval_of_expr_with_deps(n, 1);
auto interv_wd = interval_of_expr<with_deps>(n, 1);
TRACE("grobner", tout << "conflict: interv_wd = "; display(tout, interv_wd ) <<"expr = " << *n << "\n, initial deps\n"; print_dependencies(initial_deps, tout););
check_interval_for_conflict_on_zero(interv_wd, initial_deps);
reset(); // clean the memory allocated by the interval bound dependencies
return true;
}
intervals::interv intervals::interval_of_sum_no_term_with_deps(const nex_sum* e) {
const nex* inf_e = get_inf_interval_child(e);
if (inf_e) {
return interv();
}
auto & es = *e;
interv a = interval_of_expr_with_deps(es[0], 1);
for (unsigned k = 1; k < es.size(); k++) {
TRACE("nla_intervals_details_sum", tout << "es[" << k << "]= " << *es[k] << "\n";);
interv b = interval_of_expr_with_deps(es[k], 1);
interv c;
interval_deps_combine_rule combine_rule;
TRACE("nla_intervals_details_sum", tout << "a = "; display(tout, a) << "\nb = "; display(tout, b) << "\n";);
add(a, b, c, combine_rule);
combine_deps(a, b, combine_rule, c);
set_with_deps(a, c);
TRACE("nla_intervals_details_sum", tout << *es[k] << ", ";
display(tout, a); tout << "\n";);
}
TRACE("nla_intervals_details", tout << "e=" << *e << "\n";
tout << " interv = "; display(tout, a););
return a;
}
intervals::interv intervals::interval_of_sum_no_term(const nex_sum* e) {
const nex* inf_e = get_inf_interval_child(e);
if (inf_e) {
return interv();
}
auto & es = *e;
interv a = interval_of_expr(es[0], 1);
for (unsigned k = 1; k < es.size(); k++) {
TRACE("nla_intervals_details_sum", tout << "es[" << k << "]= " << *es[k] << "\n";);
interv b = interval_of_expr(es[k], 1);
interv c;
TRACE("nla_intervals_details_sum", tout << "a = "; display(tout, a) << "\nb = "; display(tout, b) << "\n";);
add(a, b, c);
set_with_no_deps(a, c);
TRACE("nla_intervals_details_sum", tout << *es[k] << ", ";
display(tout, a); tout << "\n";);
}
TRACE("nla_intervals_details", tout << "e=" << *e << "\n";
tout << " interv = "; display(tout, a););
return a;
}
void intervals::add_mul_of_degree_one_to_vector(const nex_mul* e, vector<std::pair<rational, lpvar>> &v) {
TRACE("nla_horner_details", tout << *e << "\n";);
SASSERT(e->size() == 1);
@ -351,7 +126,7 @@ lp::lar_term intervals::expression_to_normalized_term(const nex_sum* e, rational
unsigned a_index;
for (const nex* c : *e) {
if (c->is_scalar()) {
b += to_scalar(c)->value();
b += c->to_scalar().value();
} else {
add_linear_to_vector(c, v);
if (v.empty())
@ -367,8 +142,7 @@ lp::lar_term intervals::expression_to_normalized_term(const nex_sum* e, rational
lp::lar_term t;
if (a.is_one()) {
for (unsigned k = 0; k < v.size(); k++) {
auto& p = v[k];
for (auto& p : v) {
t.add_coeff_var(p.first, p.second);
}
} else {
@ -398,126 +172,6 @@ lpvar intervals::find_term_column(const lp::lar_term & norm_t, rational& a) cons
return -1;
}
bool intervals::interval_from_term_with_deps(const nex* e, interv & i) const {
rational a, b;
lp::lar_term norm_t = expression_to_normalized_term(to_sum(e), a, b);
lp::explanation exp;
if (m_core->explain_by_equiv(norm_t, exp)) {
set_zero_interval_with_explanation(i, exp);
TRACE("nla_intervals", tout << "explain_by_equiv\n";);
return true;
}
lpvar j = find_term_column(norm_t, a);
if (j + 1 == 0)
return false;
set_var_interval_with_deps(j, i);
interv bi;
mul_with_deps(a, i, bi);
add(b, bi);
set_with_deps(i, bi);
TRACE("nla_intervals",
m_core->m_lar_solver.print_column_info(j, tout) << "\n";
tout << "a=" << a << ", b=" << b << "\n";
tout << *e << ", interval = "; display(tout, i););
return true;
}
bool intervals::interval_from_term(const nex* e, interv & i) const {
rational a, b;
lp::lar_term norm_t = expression_to_normalized_term(to_sum(e), a, b);
lp::explanation exp;
if (m_core->explain_by_equiv(norm_t, exp)) {
set_zero_interval(i);
TRACE("nla_intervals", tout << "explain_by_equiv\n";);
return true;
}
lpvar j = find_term_column(norm_t, a);
if (j + 1 == 0)
return false;
set_var_interval(j, i);
interv bi;
mul_no_deps(a, i, bi);
add(b, bi);
set_with_no_deps(i, bi);
TRACE("nla_intervals",
m_core->m_lar_solver.print_column_info(j, tout) << "\n";
tout << "a=" << a << ", b=" << b << "\n";
tout << *e << ", interval = "; display(tout, i););
return true;
}
intervals::interv intervals::interval_of_sum_with_deps(const nex_sum* e) {
TRACE("nla_intervals_details", tout << "e=" << *e << "\n";);
interv i_e = interval_of_sum_no_term_with_deps(e);
if (e->is_a_linear_term()) {
SASSERT(e->is_sum() && e->size() > 1);
interv i_from_term ;
if (interval_from_term_with_deps(e, i_from_term)) {
interv r = intersect_with_deps(i_e, i_from_term);
TRACE("nla_intervals_details", tout << "intersection="; display(tout, r) << "\n";);
if (is_empty(r)) {
SASSERT(false); // not implemented
}
return r;
}
}
return i_e;
}
intervals::interv intervals::interval_of_sum(const nex_sum* e) {
interv i_e = interval_of_sum_no_term(e);
TRACE("nla_intervals_details", tout << "e=" << *e << "\ni_e="; display(tout, i_e) << "\n";);
if (e->is_a_linear_term()) {
SASSERT(e->is_sum() && e->size() > 1);
interv i_from_term ;
if (interval_from_term(e, i_from_term)) {
TRACE("nla_intervals_details", tout << "i_from_term="; display(tout, i_from_term) << "\n";);
interv r = intersect(i_e, i_from_term, 44);
TRACE("nla_intervals_details", tout << "intersection="; display(tout, r) << "\n";);
if (is_empty(r)) {
SASSERT(false); // not implemented
}
return r;
}
}
return i_e;
}
void intervals::set_var_interval(lpvar v, interval& b) const {
lp::constraint_index ci;
rational val;
bool is_strict;
if (ls().has_lower_bound(v, ci, val, is_strict)) {
m_config.set_lower(b, val);
m_config.set_lower_is_open(b, is_strict);
m_config.set_lower_is_inf(b, false);
}
else {
m_config.set_lower_is_open(b, true);
m_config.set_lower_is_inf(b, true);
}
if (ls().has_upper_bound(v, ci, val, is_strict)) {
m_config.set_upper(b, val);
m_config.set_upper_is_open(b, is_strict);
m_config.set_upper_is_inf(b, false);
}
else {
m_config.set_upper_is_open(b, true);
m_config.set_upper_is_inf(b, true);
}
}
void intervals::set_zero_interval_with_explanation(interval& i, const lp::explanation& exp) const {
auto val = rational(0);
m_config.set_lower(i, val);
@ -564,7 +218,6 @@ bool intervals::separated_from_zero_on_upper(const interval& i) const {
return true;
}
bool intervals::check_interval_for_conflict_on_zero(const interval & i, ci_dependency* dep) {
return check_interval_for_conflict_on_zero_lower(i, dep) || check_interval_for_conflict_on_zero_upper(i, dep);
}