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remove dead code related to nla unit propagation

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Signed-off-by: Lev Nachmanson <levnach@hotmail.com>
This commit is contained in:
Lev Nachmanson 2023-09-19 10:56:09 -07:00
parent cf63e75898
commit c5cfd62e0a
6 changed files with 16 additions and 95 deletions
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48
src/math/lp/monomial_bounds.cpp
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@ -24,7 +24,6 @@ namespace nla {
}
}
bool monomial_bounds::is_too_big(mpq const& q) const {
return rational(q).bitsize() > 256;
}
@ -258,53 +257,6 @@ namespace nla {
}
}
void monomial_bounds::unit_propagate() {
for (lpvar v : c().m_monics_with_changed_bounds)
unit_propagate(c().emons()[v]);
c().m_monics_with_changed_bounds.clear();
}
void monomial_bounds::unit_propagate(monic const& m) {
m_propagated.reserve(m.var() + 1, false);
if (m_propagated[m.var()])
return;
lpvar non_fixed = null_lpvar, zero_var = null_lpvar;
if (!is_linear(m, zero_var, non_fixed))
return;
c().trail().push(set_bitvector_trail(m_propagated, m.var()));
if (zero_var != null_lpvar) {
new_lemma lemma(c(), "fixed-values");
lemma.explain_fixed(zero_var);
lemma += ineq(m.var(), lp::lconstraint_kind::EQ, 0);
}
else {
rational k = rational(1);
for (auto v : m)
if (v != non_fixed) {
k *= c().lra.get_column_value(v).x;
if (k.is_big()) return;
}
new_lemma lemma(c(), "fixed-values");
for (auto v : m)
if (v != non_fixed)
lemma.explain_fixed(v);
if (non_fixed != null_lpvar) {
lp::lar_term term;
term.add_var(m.var());
term.add_monomial(-k, non_fixed);
lemma += ineq(term, lp::lconstraint_kind::EQ, 0);
} else {
lemma += ineq(m.var(), lp::lconstraint_kind::EQ, k);
}
}
}
// returns true iff (all variables are fixed,
// or all but one variable are fixed) and the bounds are not big,
// or at least one variable is fixed to zero.