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fix a bug in the recursion in cross_nested

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Signed-off-by: Lev Nachmanson <levnach@hotmail.com>
This commit is contained in:
Lev Nachmanson 2019-07-19 15:15:46 -07:00
parent cef9726f00
commit d5708b184a
6 changed files with 122 additions and 162 deletions
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73
src/math/lp/cross_nested.h
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@ -30,7 +30,7 @@ public:
void run() {
vector<nex*> front;
cross_nested_of_expr_on_front_elem(&m_e, front);
cross_nested_of_expr_on_front_elem(&m_e, front, true); // true for trivial form - no change
}
static nex* pop_back(vector<nex*>& front) {
@ -69,7 +69,7 @@ public:
f.simplify();
* c = nex::mul(f, *c);
TRACE("nla_cn", tout << "common factor=" << f << ", c=" << *c << "\n";);
cross_nested_of_expr_on_front_elem(&(c->children()[1]), front);
cross_nested_of_expr_on_front_elem(&(c->children()[1]), front, false);
return true;
}
@ -89,39 +89,54 @@ public:
TRACE("nla_cn", tout << "restore c=" << *c << ", m_e=" << m_e << "\n";);
for (unsigned i = 0; i < front.size(); i++)
*(front[i]) = copy_of_front[i];
TRACE("nla_cn", tout << "restore c=" << *c << ", m_e=" << m_e << "\n";);
}
}
void cross_nested_of_expr_on_front_elem(nex* c, vector<nex*>& front) {
static std::ostream& dump_occurences(std::ostream& out, const std::unordered_map<lpvar, occ>& occurences) {
out << "{";
for(const auto& p: occurences) {
const occ& o = p.second;
out << "(" << (char)('a' + p.first) << "->" << o << ")";
}
out << "}" << std::endl;
return out;
}
void cross_nested_of_expr_on_front_elem(nex* c, vector<nex*>& front, bool trivial_form) {
SASSERT(c->is_sum());
auto occurences = get_mult_occurences(*c);
TRACE("nla_cn", tout << "m_e=" << m_e << "\nc=" << *c << "\noccurences="; print_vector(occurences, tout) << "\nfront:"; print_vector_of_ptrs(front, tout) << "\n";);
TRACE("nla_cn", tout << "m_e=" << m_e << "\nc=" << *c << ", c occurences=";
dump_occurences(tout, occurences) << "; front:"; print_vector_of_ptrs(front, tout) << "\ntrivial_form=" << trivial_form << "\n";);
if (occurences.empty()) {
if(front.empty()) {
TRACE("nla_cn_cn", tout << "got the cn form: m_e=" << m_e << "\n";);
if (trivial_form)
return;
TRACE("nla_cn", tout << "got the cn form: m_e=" << m_e << "\n";);
SASSERT(!can_be_cross_nested_more(m_e));
auto e_to_report = m_e;
e_to_report.simplify();
e_to_report.sort();
m_call_on_result(e_to_report);
m_call_on_result(e_to_report);
} else {
nex* c = pop_back(front);
cross_nested_of_expr_on_front_elem(c, front);
cross_nested_of_expr_on_front_elem(c, front, trivial_form);
}
} else {
cross_nested_of_expr_on_front_elem_occs(c, front, occurences);
}
}
static char ch(unsigned j) {
return (char)('a'+j);
}
// e is the global expression, c is the sub expressiond which is going to changed from sum to the cross nested form
void cross_nested_of_expr_on_sum_and_var(nex* c, lpvar j, vector<nex*> front) {
TRACE("nla_cn", tout << "m_e=" << m_e << "\nc=" << *c << "\nj = v" << j << "\nfront="; print_vector_of_ptrs(front, tout) << "\n";);
TRACE("nla_cn", tout << "m_e=" << m_e << "\nc=" << *c << "\nj = " << ch(j) << "\nfront="; print_vector_of_ptrs(front, tout) << "\n";);
split_with_var(*c, j, front);
TRACE("nla_cn", tout << "after split c=" << *c << "\nfront="; print_vector_of_ptrs(front, tout) << "\n";);
do {
nex* n = pop_back(front);
cross_nested_of_expr_on_front_elem(n, front);
} while (!front.empty());
TRACE("nla_cn", tout << "after split c=" << *c << "\nfront="; print_vector_of_ptrs(front, tout) << "\n";);
SASSERT(front.size());
nex* n = pop_back(front); TRACE("nla_cn", tout << "n=" << *n <<"\n";);
cross_nested_of_expr_on_front_elem(n, front, false); // we got a non-trivial_form
}
static void process_var_occurences(lpvar j, std::unordered_map<lpvar, occ>& occurences) {
auto it = occurences.find(j);
@ -131,17 +146,7 @@ public:
} else {
occurences.insert(std::make_pair(j, occ(1, 1)));
}
}
static void dump_occurences(std::ostream& out, const std::unordered_map<lpvar, occ>& occurences) {
out << "{";
for(const auto& p: occurences) {
const occ& o = p.second;
out << "(v" << p.first << "->" << o << ")";
}
out << "}" << std::endl;
}
}
static void update_occurences_with_powers(std::unordered_map<lpvar, occ>& occurences,
const std::unordered_map<lpvar, int>& powers) {
@ -156,6 +161,7 @@ public:
it->second.m_power = std::min(it->second.m_power, jp);
}
}
TRACE("nla_cn_details", tout << "occs="; dump_occurences(tout, occurences) << "\n";);
}
static void remove_singular_occurences(std::unordered_map<lpvar, occ>& occurences) {
@ -173,7 +179,6 @@ public:
std::unordered_map<lpvar, occ> occurences;
SASSERT(e.type() == expr_type::SUM);
for (const auto & ce : e.children()) {
std::unordered_set<lpvar> seen;
if (ce.is_mul()) {
auto powers = ce.get_powers_from_mul();
update_occurences_with_powers(occurences, powers);
@ -182,16 +187,20 @@ public:
}
}
remove_singular_occurences(occurences);
TRACE("nla_cn_details", dump_occurences(tout, occurences););
TRACE("nla_cn_details", tout << "e=" << e << "\noccs="; dump_occurences(tout, occurences) << "\n";);
return occurences;
}
bool can_be_cross_nested_more(const nex& e) const {
bool can_be_cross_nested_more(const nex& s) const {
auto e = s;
e.simplify();
TRACE("nla_cn_details", tout << "simplified " << e << "\n";);
switch (e.type()) {
case expr_type::SCALAR:
return false;
case expr_type::SUM: {
return !get_mult_occurences(e).empty();
}
case expr_type::SUM:
if ( !get_mult_occurences(e).empty())
return true;
// fall through MUL
case expr_type::MUL:
{
for (const auto & c: e.children()) {