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move interval functionality from horner to intervals

Signed-off-by: Lev Nachmanson <levnach@hotmail.com>
This commit is contained in:
Lev Nachmanson 2019-10-28 16:47:53 -07:00
parent b84ac3f27e
commit 9b3ebfdd2a
4 changed files with 477 additions and 473 deletions

View file

@ -32,6 +32,459 @@ void intervals::set_var_interval_with_deps(lpvar v, interval& b) const {
}
}
void intervals::set_interval_for_scalar(interv& a, const rational& v) {
set_lower(a, v);
set_upper(a, v);
set_lower_is_open(a, false);
set_lower_is_inf(a, false);
set_upper_is_open(a, false);
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->children()) {
if (has_inf_interval(c))
return c;
}
return nullptr;
}
bool intervals::mul_has_inf_interval(const nex_mul* e) const {
bool has_inf = false;
for (const auto & p : e->children()) {
const nex *c = p.e();
if (!c->is_elementary())
return false;
if (has_zero_interval(c))
return false;
has_inf |= has_inf_interval(c);
}
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())
return false;
for (auto * c : to_sum(e)->children()) {
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());
if (! e->is_var())
return false;
return m_core->var_is_fixed_to_zero(to_var(e)->var());
}
const nex* intervals::get_zero_interval_child(const nex_mul* e) const {
for (const auto & p : e->children()) {
const nex * c = p.e();
if (has_zero_interval(c))
return c;
}
return nullptr;
}
intervals::interv intervals::interval_of_mul_with_deps(const nex_mul* e) {
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;
}
SASSERT(e->is_mul());
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(a, c, 33);
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;
}
bool intervals::check_cross_nested_expr(const nex* n, ci_dependency* initial_deps) {
TRACE("nla_intervals", tout << "cross-nested n = " << *n << ", n->type() == " << n->type() << "\n";);
m_core->lp_settings().stats().m_cross_nested_forms++;
auto i = interval_of_expr(n, 1);
TRACE("nla_intervals", tout << "callback n = " << *n << "\ni="; display(tout, i) << "\n";);
if (!separated_from_zero(i)) {
reset();
return false;
}
auto interv_wd = interval_of_expr_with_deps(n, 1);
TRACE("nla_intervals", tout << "conflict: interv_wd = "; display(tout, interv_wd ) << *n << "\n";);
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->children();
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->children();
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;
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(a, c, 22);
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);
SASSERT((*e)[0].pow() == 1);
const nex *ev = (*e)[0].e();
lpvar j = to_var(ev)->var();
v.push_back(std::make_pair(e->coeff(), j));
}
void intervals::add_linear_to_vector(const nex* e, vector<std::pair<rational, lpvar>> &v) {
TRACE("nla_horner_details", tout << *e << "\n";);
switch (e->type()) {
case expr_type::MUL:
add_mul_of_degree_one_to_vector(to_mul(e), v);
break;
case expr_type::VAR:
v.push_back(std::make_pair(rational(1), to_var(e)->var()));
break;
default:
SASSERT(!e->is_sum());
// noop
}
}
// 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";);
lpvar smallest_j;
vector<std::pair<rational, lpvar>> v;
b = rational(0);
unsigned a_index;
for (const nex* c : e->children()) {
if (c->is_scalar()) {
b += to_scalar(c)->value();
} else {
add_linear_to_vector(c, v);
if (v.empty())
continue;
if (v.size() == 1 || smallest_j > v.back().second) {
smallest_j = v.back().second;
a_index = v.size() - 1;
}
}
}
TRACE("nla_horner_details", tout << "a_index = " << a_index << ", v="; print_vector(v, tout) << "\n";);
a = v[a_index].first;
lp::lar_term t;
if (a.is_one()) {
for (unsigned k = 0; k < v.size(); k++) {
auto& p = v[k];
t.add_coeff_var(p.first, p.second);
}
} else {
for (unsigned k = 0; k < v.size(); k++) {
auto& p = v[k];
if (k != a_index)
t.add_coeff_var(p.first/a, p.second);
else
t.add_var(p.second);
}
}
TRACE("nla_horner_details", tout << a << "* (";
lp::lar_solver::print_term_as_indices(t, tout) << ") + " << b << std::endl;);
SASSERT(t.is_normalized());
return t;
}
// we should have in the case of found a * m_terms[k] + b = e,
// where m_terms[k] corresponds to the returned lpvar
lpvar intervals::find_term_column(const lp::lar_term & norm_t, rational& a) const {
std::pair<rational, lpvar> a_j;
if (m_core->m_lar_solver.fetch_normalized_term_column(norm_t, a_j)) {
a /= a_j.first;
return a_j.second;
}
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(i, bi, 44);
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;