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operate with sign as a boolean

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Signed-off-by: Lev Nachmanson <levnach@hotmail.com>
This commit is contained in:
Lev Nachmanson 2019-05-06 16:44:48 -07:00
parent 6d5fd5d980
commit 495161fe5c
9 changed files with 57 additions and 65 deletions
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22
src/util/lp/nla_basics_lemmas.cpp
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@ -27,7 +27,7 @@ basics::basics(core * c) : common(c) {}
// Monomials m and n vars have the same values, up to "sign"
// Generate a lemma if values of m.var() and n.var() are not the same up to sign
bool basics::basic_sign_lemma_on_two_monomials(const monomial& m, const monomial& n) {
const rational& sign = m.rsign() * n.rsign();
const rational sign = sign_to_rat(m.rsign() ^ n.rsign());
if (val(m) == val(n) * sign)
return false;
TRACE("nla_solver", tout << "sign contradiction:\nm = " << pp_mon(c(), m) << "n= " << pp_mon(c(), n) << "sign: " << sign << "\n";);
@ -478,14 +478,25 @@ void basics::generate_pl(const monomial& rm, const factorization& fc, int factor
explain(rm);
}
TRACE("nla_solver", c().print_lemma(tout); );
}
}
bool basics::is_separated_from_zero(const factorization& f) const {
for (const factor& fc: f) {
lpvar j = var(fc);
if (!(c().var_has_positive_lower_bound(j) || c().var_has_negative_upper_bound(j))) {
return false;
}
}
return true;
}
// here we use the fact xy = 0 -> x = 0 or y = 0
void basics::basic_lemma_for_mon_zero_model_based(const monomial& rm, const factorization& f) {
TRACE("nla_solver", c().trace_print_monomial_and_factorization(rm, f, tout););
SASSERT(val(rm).is_zero()&& ! c().rm_check(rm));
add_empty_lemma();
int sign = c().get_derived_sign(rm, f);
if (sign == 0) {
if (is_separated_from_zero(f)) {
c().mk_ineq(var(rm), llc::NE);
for (auto j : f) {
c().mk_ineq(var(j), llc::EQ);
@ -496,7 +507,6 @@ void basics::basic_lemma_for_mon_zero_model_based(const monomial& rm, const fact
c().explain_separation_from_zero(var(j));
}
}
explain(rm);
explain(f);
TRACE("nla_solver", c().print_lemma(tout););
}
@ -692,7 +702,7 @@ void basics::basic_lemma_for_mon_neutral_model_based(const monomial& rm, const f
// use the fact
// 1 * 1 ... * 1 * x * 1 ... * 1 = x
bool basics::basic_lemma_for_mon_neutral_from_factors_to_monomial_model_based(const monomial& rm, const factorization& f) {
rational sign = rm.rsign();
rational sign = sign_to_rat(rm.rsign());
TRACE("nla_solver_bl", tout << "f = "; c().print_factorization(f, tout); tout << ", sign = " << sign << '\n'; );
lpvar not_one = -1;
for (auto j : f){