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fixes in horner's heuristic

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Signed-off-by: Lev Nachmanson <levnach@hotmail.com>
This commit is contained in:
Lev Nachmanson 2019-08-07 11:40:39 -07:00
parent 207c1c509f
commit 1b8b09cddb
6 changed files with 145 additions and 69 deletions
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28
src/math/lp/horner.cpp
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@ -283,10 +283,18 @@ lp::lar_term horner::expression_to_normalized_term(nex& e, rational& a, rational
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 horner::find_term_column(const nex& e, rational& a, rational& b) const {
nex n = e;
lp::lar_term norm_t = expression_to_normalized_term(n, a, b);
return c().m_lar_solver.fetch_normalized_term_column(norm_t);
std::pair<rational, lpvar> a_j;
if (c().m_lar_solver.fetch_normalized_term_column(norm_t, a_j)) {
a /= a_j.first;
return a_j.second;
}
return -1;
}
interv horner::interval_of_sum_no_terms(const nex& e) {
@ -350,12 +358,16 @@ interv horner::interval_of_sum(const nex& e) {
interv i_e = interval_of_sum_no_terms(e);
if (e.sum_is_a_linear_term()) {
interv i_from_term ;
if (interval_from_term(e, i_from_term)
&&
is_tighter(i_from_term, i_e))
return i_from_term;
if (interval_from_term(e, i_from_term)) {
interv r = m_intervals.intersect(i_e, i_from_term);
TRACE("nla_horner_details", tout << "intersection="; m_intervals.display(tout, r) << "\n";);
if (m_intervals.is_empty(r)) {
SASSERT(false); // not implemented
}
return r;
}
}
return i_e;
}
@ -365,10 +377,6 @@ void horner::set_var_interval(lpvar v, interv& b) const{
TRACE("nla_horner_details_var", tout << "v = "; print_var(v, tout) << "\n"; m_intervals.display(tout, b););
}
bool horner::is_tighter(const interv& a, const interv& b) const {
return m_intervals.is_tighter(a, b);
}
}