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handle the empty intersection in nla_intervals

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Signed-off-by: Lev Nachmanson <levnach@hotmail.com>
This commit is contained in:
Lev Nachmanson 2020-04-08 14:29:09 -07:00
parent 6e8d9001dc
commit 4621767968
2 changed files with 83 additions and 47 deletions
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112
src/math/lp/nla_intervals.cpp
View file

@ -69,34 +69,40 @@ std::ostream & intervals::print_dependencies(u_dependency* deps , std::ostream&
return out;
}
std::ostream& intervals::display_separating_interval(std::ostream& out, const nex*n, const scoped_dep_interval& interv_wd, u_dependency* initial_deps) {
out << "conflict: interv_wd = "; display(out, interv_wd ) <<"expr = " << *n << "\n, initial deps\n"; print_dependencies(initial_deps, out);
out << ", expressions vars = \n";
for(lpvar j: m_core->get_vars_of_expr_with_opening_terms(n)) {
m_core->print_var(j, out);
}
out << "\n";
return out;
}
// return true iff the interval of n is does not contain 0
bool intervals::check_nex(const nex* n, u_dependency* initial_deps) {
m_core->lp_settings().stats().m_cross_nested_forms++;
scoped_dep_interval i(get_dep_intervals());
interval_of_expr<e_with_deps::without_deps>(n, 1, i);
if (!m_dep_intervals.separated_from_zero(i)) {
return false;
}
scoped_dep_interval interv_wd(get_dep_intervals());
interval_of_expr<e_with_deps::with_deps>(n, 1, interv_wd);
TRACE("grobner", tout << "conflict: interv_wd = "; display(tout, interv_wd ) <<"expr = " << *n << "\n, initial deps\n"; print_dependencies(initial_deps, tout);
tout << ", expressions vars = \n";
for(lpvar j: m_core->get_vars_of_expr_with_opening_terms(n)) {
m_core->print_var(j, tout);
}
tout << "\n";
);
std::function<void (const lp::explanation&)> f = [this](const lp::explanation& e) {
m_core->add_empty_lemma();
m_core->current_expl().add(e);
};
if (!interval_of_expr<e_with_deps::without_deps>(n, 1, i, f)) {
// found a conflict during the interval calculation
return true;
}
if (!m_dep_intervals.separated_from_zero(i)) {
return false;
}
scoped_dep_interval interv_wd(get_dep_intervals());
interval_of_expr<e_with_deps::with_deps>(n, 1, interv_wd, f);
TRACE("nla_intervals", display_separating_interval(tout, n, interv_wd, initial_deps););
m_dep_intervals.check_interval_for_conflict_on_zero(interv_wd, initial_deps, f);
return true;
}
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";);
TRACE("nla_intervals_details", tout << *e << "\n";);
SASSERT(e->size() == 1);
SASSERT((*e)[0].pow() == 1);
const nex *ev = (*e)[0].e();
@ -105,7 +111,7 @@ void intervals::add_mul_of_degree_one_to_vector(const nex_mul* e, vector<std::pa
}
void intervals::add_linear_to_vector(const nex* e, vector<std::pair<rational, lpvar>> &v) {
TRACE("nla_horner_details", tout << *e << "\n";);
TRACE("nla_intervals_details", tout << *e << "\n";);
switch (e->type()) {
case expr_type::MUL:
add_mul_of_degree_one_to_vector(to_mul(e), v);
@ -121,7 +127,7 @@ void intervals::add_linear_to_vector(const nex* e, vector<std::pair<rational, lp
// e = a * can_t + b
lp::lar_term intervals::expression_to_normalized_term(const nex_sum* e, rational& a, rational& b) {
TRACE("nla_horner_details", tout << *e << "\n";);
TRACE("nla_intervals_details", tout << *e << "\n";);
lpvar smallest_j = 0;
vector<std::pair<rational, lpvar>> v;
b = rational(0);
@ -139,7 +145,7 @@ lp::lar_term intervals::expression_to_normalized_term(const nex_sum* e, rational
}
}
}
TRACE("nla_horner_details", tout << "a_index = " << a_index << ", v="; print_vector(v, tout) << "\n";);
TRACE("nla_intervals_details", tout << "a_index = " << a_index << ", v="; print_vector(v, tout) << "\n";);
a = v[a_index].first;
lp::lar_term t;
@ -156,7 +162,7 @@ lp::lar_term intervals::expression_to_normalized_term(const nex_sum* e, rational
t.add_var(p.second);
}
}
TRACE("nla_horner_details", tout << a << "* (";
TRACE("nla_intervals_details", tout << a << "* (";
lp::lar_solver::print_term_as_indices(t, tout) << ") + " << b << std::endl;);
SASSERT(t.is_normalized());
return t;
@ -303,21 +309,24 @@ bool intervals::interval_from_term(const nex& e, scoped_dep_interval& i) {
return true;
}
template <e_with_deps wd>
void intervals::interval_of_sum_no_term(const nex_sum& e, scoped_dep_interval & sdi) {
template <e_with_deps wd, typename T>
bool intervals::interval_of_sum_no_term(const nex_sum& e, scoped_dep_interval & sdi, const std::function<void (const T&)>& f) {
if (has_inf_interval(e)) {
SASSERT(m_dep_intervals.lower_is_inf(sdi) && m_dep_intervals.upper_is_inf(sdi));
return;
return true; // no conflict
}
interval_of_expr<wd>(e[0], 1, sdi);
if (!interval_of_expr<wd>(e[0], 1, sdi, f))
return false;
for (unsigned k = 1; k < e.size(); k++) {
TRACE("nla_intervals_details_sum", tout << "e[" << k << "]= " << *e[k] << "\n";);
TRACE("nla_intervals_details", tout << "e[" << k << "]= " << *e[k] << "\n";);
scoped_dep_interval b(get_dep_intervals());
interval_of_expr<wd>(e[k], 1, b);
if (!interval_of_expr<wd>(e[k], 1, b, f)) {
return false;
}
scoped_dep_interval c(get_dep_intervals());
TRACE("nla_intervals_details_sum", tout << "sdi = "; display(tout, sdi) << "\nb = "; display(tout, b) << "\n";);
TRACE("nla_intervals_details", tout << "sdi = "; display(tout, sdi) << "\nb = "; display(tout, b) << "\n";);
if (wd == e_with_deps::with_deps) {
interval_deps_combine_rule combine_rule;
m_dep_intervals.add(sdi, b, c, combine_rule);
@ -327,47 +336,68 @@ void intervals::interval_of_sum_no_term(const nex_sum& e, scoped_dep_interval &
m_dep_intervals.add(sdi, b, c);
}
m_dep_intervals.set<wd>(sdi, c);
TRACE("nla_intervals_details_sum", tout << *e[k] << ", ";
TRACE("nla_intervals_details", tout << *e[k] << ", ";
display(tout, sdi); tout << "\n";);
}
TRACE("nla_intervals_details", tout << "e=" << e << "\n";
tout << " interv = "; display(tout, sdi););
return true; // no conflict
}
template <e_with_deps wd>
void intervals::interval_of_sum(const nex_sum& e, scoped_dep_interval& a) {
template <e_with_deps wd, typename T>
bool intervals::interval_of_sum(const nex_sum& e, scoped_dep_interval& a, const std::function<void (const T&)>& f) {
TRACE("nla_intervals_details", tout << "e=" << e << "\n";);
interval_of_sum_no_term<wd>(e, a);
if(! interval_of_sum_no_term<wd>(e, a, f)) {
return false;
}
if (e.is_a_linear_term()) {
SASSERT(e.is_sum() && e.size() > 1);
scoped_dep_interval i_from_term(get_dep_intervals());
if (interval_from_term<wd>(e, i_from_term)) {
interval r = m_dep_intervals.intersect<wd>(a, i_from_term);
TRACE("nla_intervals_details", tout << "intersection="; display(tout, r) << "\n";);
if (m_dep_intervals.is_empty(r)) {
SASSERT(false); // not implemented
TRACE("nla_intervals_details", tout << "empty\n";);
if (wd == e_with_deps::with_deps) {
T expl;
get_dep_intervals().linearize(r.m_upper_dep, expl);
get_dep_intervals().linearize(r.m_lower_dep, expl);
f(expl);
} else {
// need to recalculate the interval with dependencies
scoped_dep_interval sa(get_dep_intervals());
interval_of_sum<e_with_deps::with_deps>(e, sa, f);
}
return false;
}
m_dep_intervals.set<wd>(a, r);
}
}
return true;
}
template <e_with_deps wd>
void intervals::interval_of_mul(const nex_mul& e, scoped_dep_interval& a) {
template <e_with_deps wd, typename T>
bool intervals::interval_of_mul(const nex_mul& e, scoped_dep_interval& a, const std::function<void (const T&)>& f) {
TRACE("nla_intervals_details", tout << "e = " << e << "\n";);
const nex* zero_interval_child = get_zero_interval_child(e);
if (zero_interval_child) {
interval_of_expr<wd>(zero_interval_child, 1, a);
bool r = interval_of_expr<wd>(zero_interval_child, 1, a, f);
SASSERT(r);
(void)r;
if(wd == e_with_deps::with_deps)
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 true; // regural calculation: no conflict
}
m_dep_intervals.set_interval_for_scalar(a, e.coeff());
TRACE("nla_intervals_details", tout << "a = "; display(tout, a); );
for (const auto& ep : e) {
scoped_dep_interval b(get_dep_intervals());
interval_of_expr<wd>(ep.e(), ep.pow(), b);
if (!interval_of_expr<wd>(ep.e(), ep.pow(), b, f))
return false;
TRACE("nla_intervals_details", tout << "ep = " << ep << ", "; display(tout, b); );
scoped_dep_interval c(get_dep_intervals());
if (wd == e_with_deps::with_deps) {
@ -385,6 +415,7 @@ void intervals::interval_of_mul(const nex_mul& e, scoped_dep_interval& a) {
}
TRACE("nla_intervals_details", tout << "e=" << e << "\n";
tout << " return "; display(tout, a););
return true;
}
template <e_with_deps wd>
@ -394,8 +425,8 @@ void intervals::to_power(scoped_dep_interval& a, unsigned p) {
m_dep_intervals.set<wd>(a, b);
}
template <e_with_deps wd>
void intervals::interval_of_expr(const nex* e, unsigned p, scoped_dep_interval& a) {
template <e_with_deps wd, typename T>
bool intervals::interval_of_expr(const nex* e, unsigned p, scoped_dep_interval& a, const std::function<void (const T&)>& f) {
switch (e->type()) {
case expr_type::SCALAR:
{
@ -403,14 +434,16 @@ void intervals::interval_of_expr(const nex* e, unsigned p, scoped_dep_interval&
}
break;
case expr_type::SUM: {
interval_of_sum<wd>(e->to_sum(), a);
if (!interval_of_sum<wd>(e->to_sum(), a, f))
return false;
if (p != 1) {
to_power<wd>(a, p);
}
break;
}
case expr_type::MUL: {
interval_of_mul<wd>(e->to_mul(), a);
if (!interval_of_mul<wd>(e->to_mul(), a, f))
return false;
if (p != 1) {
to_power<wd>(a, p);
}
@ -426,6 +459,7 @@ void intervals::interval_of_expr(const nex* e, unsigned p, scoped_dep_interval&
TRACE("nla_intervals_details", tout << e->type() << "\n";);
UNREACHABLE();
}
return true; // no conflict
}

18
src/math/lp/nla_intervals.h
View file

@ -67,19 +67,20 @@ public:
bool interval_from_term(const nex& e, scoped_dep_interval& i);
template <dep_intervals::with_deps_t wd>
void interval_of_sum_no_term(const nex_sum& e, scoped_dep_interval&);
template <dep_intervals::with_deps_t wd, typename T>
bool interval_of_sum_no_term(const nex_sum& e, scoped_dep_interval&, const std::function<void (const T&)>& f );
template <dep_intervals::with_deps_t wd>
void interval_of_sum(const nex_sum& e, scoped_dep_interval&);
template <dep_intervals::with_deps_t wd, typename T>
bool interval_of_sum(const nex_sum& e, scoped_dep_interval&, const std::function<void (const T&)>& );
template <dep_intervals::with_deps_t wd>
void interval_of_mul(const nex_mul& e, scoped_dep_interval&);
template <dep_intervals::with_deps_t wd, typename T>
bool interval_of_mul(const nex_mul& e, scoped_dep_interval&, const std::function<void (const T&)>&);
template <dep_intervals::with_deps_t wd>
void to_power(scoped_dep_interval&, unsigned);
template <dep_intervals::with_deps_t wd>
void interval_of_expr(const nex* e, unsigned p, scoped_dep_interval&);
template <dep_intervals::with_deps_t wd, typename T>
bool interval_of_expr(const nex* e, unsigned p, scoped_dep_interval&, const std::function<void (const T&)>& f);
bool upper_is_inf(const interval& a) const { return m_dep_intervals.upper_is_inf(a); }
bool lower_is_inf(const interval& a) const { return m_dep_intervals.lower_is_inf(a); }
@ -98,5 +99,6 @@ public:
static void add_linear_to_vector(const nex*, vector<std::pair<rational, lpvar>>&);
static void add_mul_of_degree_one_to_vector(const nex_mul*, vector<std::pair<rational, lpvar>>&);
lpvar find_term_column(const lp::lar_term&, rational& a) const;
std::ostream& display_separating_interval(std::ostream& out, const nex*n, const scoped_dep_interval& interv_wd, u_dependency* initial_deps);
}; // end of intervals
} // end of namespace nla