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fixes in order lemmas and printing terms

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Signed-off-by: Lev Nachmanson <levnach@hotmail.com>
This commit is contained in:
Lev Nachmanson 2020-03-23 11:18:56 -07:00
parent 4b8a063996
commit 38eca3b66a
9 changed files with 83 additions and 89 deletions
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86
src/math/lp/nla_order_lemmas.cpp
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@ -255,20 +255,12 @@ bool order::order_lemma_on_ac_explore(const monic& rm, const factorization& ac,
return false;
}
// |c_sign| = 1, and c*c_sign > 0
// ac > bc && ac/|c| > bc/|c| => a*c_sign > b*c_sign
void order::generate_ol(const monic& ac,
const factor& a,
int c_sign,
const factor& c,
const monic& bc,
const factor& b,
llc ab_cmp) {
rational rc_sign = rational(c_sign);
rational sign_a = rc_sign * sign_to_rat(canonize_sign(a));
rational sign_b = rc_sign * sign_to_rat(canonize_sign(b));
rational sign_c = rc_sign * sign_to_rat(canonize_sign(c));
void order::generate_ol_eq(const monic& ac,
const factor& a,
const factor& c,
const monic& bc,
const factor& b) {
add_empty_lemma();
#if 0
IF_VERBOSE(0, verbose_stream() << var_val(ac) << "(" << mul_val(ac) << "): " << ac
@ -276,10 +268,11 @@ void order::generate_ol(const monic& ac,
<< " a " << sign_a << "*v" << var(a) << " " << val(a) << "\n"
<< " b " << sign_b << "*v" << var(b) << " " << val(b) << "\n"
<< " c " << sign_c << "*v" << var(c) << " " << val(c) << "\n");
#endif
mk_ineq(sign_c, var(c), llc::LE);
mk_ineq(canonize_sign(ac), var(ac), !canonize_sign(bc), var(bc), ab_cmp);
mk_ineq(sign_a, var(a), - sign_b, var(b), negate(ab_cmp));
#endif
// ac == bc
mk_ineq(c.var(),llc::EQ); // c is not equal to zero
mk_ineq(ac.var(), -rational(1), bc.var(), llc::NE);
mk_ineq(canonize_sign(a), a.var(), !canonize_sign(b), b.var(), llc::EQ);
explain(ac);
explain(a);
explain(bc);
@ -288,27 +281,54 @@ void order::generate_ol(const monic& ac,
TRACE("nla_solver", _().print_lemma(tout););
}
void order::generate_ol(const monic& ac,
const factor& a,
const factor& c,
const monic& bc,
const factor& b) {
add_empty_lemma();
#if 0
IF_VERBOSE(0, verbose_stream() << var_val(ac) << "(" << mul_val(ac) << "): " << ac
<< " " << ab_cmp << " " << var_val(bc) << "(" << mul_val(bc) << "): " << bc << "\n"
<< " a " << sign_a << "*v" << var(a) << " " << val(a) << "\n"
<< " b " << sign_b << "*v" << var(b) << " " << val(b) << "\n"
<< " c " << sign_c << "*v" << var(c) << " " << val(c) << "\n");
#endif
// fix the sign of c
_().negate_relation(c.var(), rational(0));
_().negate_var_relation_strictly(ac.var(), bc.var());
_().negate_var_relation_strictly(a.var(), b.var());
explain(ac);
explain(a);
explain(bc);
explain(b);
explain(c);
TRACE("nla_solver", _().print_lemma(tout););
}
// We have ac = a*c and bc = b*c.
// Suppose ac >= bc, then ac/|c| >= bc/|b|
// Notice that ac/|c| = a*rat_sign(val(c)|, and similar fo bc/|c|.//
bool order::order_lemma_on_ac_and_bc_and_factors(const monic& ac,
const factor& a,
const factor& c,
const monic& bc,
const factor& b) {
auto cv = val(c);
int c_sign = nla::rat_sign(cv);
SASSERT(c_sign != 0);
auto av_c_s = val(a)*rational(c_sign);
auto bv_c_s = val(b)*rational(c_sign);
auto acv = var_val(ac);
auto bcv = var_val(bc);
TRACE("nla_solver", _().trace_print_ol(ac, a, c, bc, b, tout););
// Suppose ac >= bc, then ac/|c| >= bc/|c|.
// Notice that ac/|c| = a*c_sign , and bc/|c| = b*c_sign, which are correspondingly av_c_s and bv_c_s
if (acv >= bcv && av_c_s < bv_c_s) {
generate_ol(ac, a, c_sign, c, bc, b, llc::LT);
return true;
} else if (acv <= bcv && av_c_s > bv_c_s) {
generate_ol(ac, a, c_sign, c, bc, b, llc::GT);
SASSERT(!val(c).is_zero());
rational c_sign = rational(nla::rat_sign(val(c)));
auto av_c_s = val(a) * c_sign;
auto bv_c_s = val(b) * c_sign;
if ((var_val(ac) > var_val(bc) && av_c_s < bv_c_s)
||
(var_val(ac) < var_val(bc) && av_c_s > bv_c_s)) {
TRACE("nla_solver", _().trace_print_ol(ac, a, c, bc, b, tout););
generate_ol(ac, a, c, bc, b);
return true;
} else {
if((var_val(ac) == var_val(bc)) && (av_c_s != bv_c_s)) {
generate_ol_eq(ac, a, c, bc, b);
}
}
return false;
}