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Signed-off-by: Lev Nachmanson <levnach@hotmail.com>
This commit is contained in:
Lev Nachmanson 2019-07-01 13:18:26 -07:00
parent 86a086b698
commit c040a0b9a5
7 changed files with 76 additions and 210 deletions
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60
src/math/lp/horner.cpp
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@ -23,7 +23,8 @@
namespace nla {
typedef nla_expr<rational> nex;
horner::horner(core * c) : common(c) {}
typedef intervals::interval interv;
horner::horner(core * c) : common(c), m_intervals(c->reslim()) {}
template <typename T>
bool horner::row_is_interesting(const T& row) const {
@ -39,7 +40,7 @@ void horner::lemma_on_row(const T& row) {
if (!row_is_interesting(row))
return;
nex e = create_expr_from_row(row);
TRACE("nla_cn", tout << "cn e = " << e << std::endl;);
TRACE("nla_cn", tout << "cross nested e = " << e << std::endl;);
intervals::interval inter = interval_of_expr(e);
check_interval_for_conflict(inter);
}
@ -95,6 +96,7 @@ void process_mul_occurences(const nex& e, std::unordered_set<lpvar>& seen, std::
}
}
// return a valid j if some variable appears more than once
unsigned horner::random_most_occured_var(std::unordered_map<lpvar, unsigned>& occurences) {
unsigned max = 0;
unsigned ret = -1;
@ -111,6 +113,8 @@ unsigned horner::random_most_occured_var(std::unordered_map<lpvar, unsigned>& oc
}
}
}
if (max <= 1)
return -1;
SASSERT(ret + 1);
return ret;
}
@ -166,12 +170,13 @@ nex horner::split_with_var(const nex& e, lpvar j) {
}
if (b.is_undef()) {
SASSERT(b.children().size() == 0);
nex r(expr_type::MUL);
r.add_child(nex::var(j));
r.add_child(a);
r.add_child(cross_nested_of_sum(a));
return r;
}
return nex::sum(nex::mul(a, nex::var(j)), b);
return nex::sum(nex::mul(cross_nested_of_sum(a), nex::var(j)), b);
}
nex horner::cross_nested_of_sum(const nex& e) {
@ -180,6 +185,7 @@ nex horner::cross_nested_of_sum(const nex& e) {
std::unordered_map<lpvar, unsigned> occurences;
get_occurences_map(e, occurences);
lpvar j = random_most_occured_var(occurences);
if (j + 1 == 0) return e;
TRACE("nla_cn",
tout << "e = " << e << "\noccurences ";
for (auto p : occurences){
@ -202,13 +208,53 @@ template <typename T> nex horner::create_expr_from_row(const T& row) {
const auto &p = *row.begin();
return nex::mul(p.coeff(), nexvar(p.var()));
}
SASSERT(false);
}
intervals::interval horner::interval_of_expr(const nex& e) {
SASSERT(false);
interv a;
switch (e.type()) {
case expr_type::SCALAR:
m_intervals.set_lower(a, e.value());
m_intervals.set_upper(a, e.value());
return a;
case expr_type::SUM:
return interval_of_sum(e.children());
case expr_type::MUL:
return interval_of_mul(e.children());
case expr_type::VAR:
return interval_of_var(e.var());
default:
TRACE("nla_cn", tout << e.type() << "\n";);
SASSERT(false);
return e;
}
}
void horner::set_var_interval(lpvar v, interv& b) {
const auto& ls = c().m_lar_solver;
lp::constraint_index ci;
rational val;
bool is_strict;
if (ls.has_lower_bound(v, ci, val, is_strict)) {
m_intervals.set_lower(b, val);
m_intervals.set_lower_is_open(b, is_strict);
m_intervals.set_lower_is_inf(b, false);
}
else {
m_intervals.set_lower_is_open(b, true);
m_intervals.set_lower_is_inf(b, true);
}
if (ls.has_upper_bound(v, ci, val, is_strict)) {
m_intervals.set_upper(b, val);
m_intervals.set_upper_is_open(b, is_strict);
m_intervals.set_upper_is_inf(b, false);
}
else {
m_intervals.set_upper_is_open(b, true);
m_intervals.set_upper_is_inf(b, true);
}
}
void horner::check_interval_for_conflict(const intervals::interval&) {
SASSERT(false);
}