mirrors/z3
3
0
Fork 0
mirror of https://github.com/Z3Prover/z3 synced 2025-04-27 02:45:51 +00:00
Code Activity

propagate only one non-fixed monomial intrernally

Browse source 
lar_solver
This commit is contained in:
Lev Nachmanson 2023-09-28 17:24:34 -07:00
parent 29b5c47a8d
commit f30a2c13be
4 changed files with 23 additions and 82 deletions
Download patch file Download diff file Expand all files Collapse all files

20
src/math/lp/monomial_bounds.cpp
View file

@ -12,6 +12,26 @@
#include "math/lp/nla_intervals.h"
namespace nla {
// here non_fixed is the only non-fixed variable in the monomial,
// vars is the vector of the monomial variables,
// k is the product of all fixed variables in vars
void monomial_bounds::propagate_nonfixed(lpvar monic_var, const svector<lpvar>& vars, lpvar non_fixed, const rational& k) {
vector<std::pair<lp::mpq, unsigned>> coeffs;
coeffs.push_back(std::make_pair(-k, non_fixed));
coeffs.push_back(std::make_pair(rational::one(), monic_var));
lp::lpvar term_index = c().lra.add_term(coeffs, UINT_MAX);
auto* dep = explain_fixed(vars, non_fixed);
term_index = c().lra.map_term_index_to_column_index(term_index);
c().lra.update_column_type_and_bound(term_index, lp::lconstraint_kind::EQ, mpq(0), dep);
}
u_dependency* monomial_bounds::explain_fixed(const svector<lpvar>& vars, lpvar non_fixed) {
u_dependency* dep = nullptr;
for (auto v : vars)
if (v != non_fixed)
dep = c().lra.join_deps(dep, c().lra.get_bound_constraint_witnesses_for_column(v));
return dep;
}
monomial_bounds::monomial_bounds(core* c):
common(c),

4
src/math/lp/monomial_bounds.h
View file

@ -17,7 +17,7 @@ namespace nla {
class monomial_bounds : common {
dep_intervals& dep;
u_dependency* explain_fixed(const svector<lpvar>& vars, lpvar non_fixed);
void var2interval(lpvar v, scoped_dep_interval& i);
bool is_too_big(mpq const& q) const;
bool propagate_value(dep_interval& range, lpvar v);
@ -35,6 +35,6 @@ namespace nla {
public:
monomial_bounds(core* core);
void propagate();
void propagate_nonfixed(lpvar monic_var, const svector<lpvar>& vars, lpvar non_fixed, const rational& k);
};
}

80
src/math/lp/nla_core.cpp
View file

@ -1912,84 +1912,6 @@ void core::add_lower_bound_monic(lpvar j, const lp::mpq& v, bool is_strict, std:
}
}
void core::propagate_monic_with_non_fixed(lpvar monic_var, const svector<lpvar>& vars, lpvar non_fixed, const rational& k) {
if (params().arith_nl_use_lemmas_in_unit_prop()) {
propagate_monic_non_fixed_with_lemma(monic_var, vars, non_fixed, k);
return;
}
lp::impq bound_value;
bool is_strict;
auto& lps = lra;
if (lower_bound_is_available(non_fixed)) {
bound_value = lra.column_lower_bound(non_fixed);
is_strict = !bound_value.y.is_zero();
auto lambda = [vars, non_fixed, &lps]() {
u_dependency* dep = lps.get_column_lower_bound_witness(non_fixed);
for (auto v : vars)
if (v != non_fixed)
dep = lps.join_deps(dep, lps.get_bound_constraint_witnesses_for_column(v));
return dep;
};
if (k.is_pos())
add_lower_bound_monic(monic_var, k * bound_value.x, is_strict, lambda);
else
add_upper_bound_monic(monic_var, k * bound_value.x, is_strict, lambda);
}
if (upper_bound_is_available(non_fixed)) {
bound_value = lra.column_upper_bound(non_fixed);
is_strict = !bound_value.y.is_zero();
auto lambda = [vars, non_fixed, &lps]() {
u_dependency* dep = lps.get_column_upper_bound_witness(non_fixed);
for (auto v : vars)
if (v != non_fixed)
dep = lps.join_deps(dep, lps.get_bound_constraint_witnesses_for_column(v));
return dep;
};
if (k.is_neg())
add_lower_bound_monic(monic_var, k * bound_value.x, is_strict, lambda);
else
add_upper_bound_monic(monic_var, k * bound_value.x, is_strict, lambda);
}
if (lower_bound_is_available(monic_var)) {
auto lambda = [vars, monic_var, non_fixed, &lps]() {
u_dependency* dep = lps.get_column_lower_bound_witness(monic_var);
for (auto v : vars) {
if (v != non_fixed) {
dep = lps.join_deps(dep, lps.get_bound_constraint_witnesses_for_column(v));
}
}
return dep;
};
bound_value = lra.column_lower_bound(monic_var);
is_strict = !bound_value.y.is_zero();
if (k.is_pos())
add_lower_bound_monic(non_fixed, bound_value.x / k, is_strict, lambda);
else
add_upper_bound_monic(non_fixed, bound_value.x / k, is_strict, lambda);
}
if (upper_bound_is_available(monic_var)) {
bound_value = lra.column_upper_bound(monic_var);
is_strict = !bound_value.y.is_zero();
auto lambda = [vars, monic_var, non_fixed, &lps]() {
u_dependency* dep = lps.get_column_upper_bound_witness(monic_var);
for (auto v : vars) {
if (v != non_fixed) {
dep = lps.join_deps(dep, lps.get_bound_constraint_witnesses_for_column(v));
}
}
return dep;
};
if (k.is_neg())
add_lower_bound_monic(non_fixed, bound_value.x / k, is_strict, lambda);
else
add_upper_bound_monic(non_fixed, bound_value.x / k, is_strict, lambda);
}
}
void core::propagate_monic_with_all_fixed(lpvar monic_var, const svector<lpvar>& vars, const rational& k) {
auto* lps = &lra;
auto lambda = [vars, lps]() { return lps->get_bound_constraint_witnesses_for_columns(vars); };
@ -2049,7 +1971,7 @@ void core::add_lower_bound_monic(lpvar j, const lp::mpq& v, bool is_strict, std:
}
if (non_fixed != null_lpvar)
propagate_monic_with_non_fixed(monic_var, vars, non_fixed, k);
m_monomial_bounds.propagate_nonfixed(monic_var, vars, non_fixed, k);
else // all variables are fixed
propagate_monic_with_all_fixed(monic_var, vars, k);
}

1
src/math/lp/nla_core.h
View file

@ -435,7 +435,6 @@ public:
bool is_linear(const svector<lpvar>& m, lpvar& zero_var, lpvar& non_fixed);
void add_bounds_for_zero_var(lpvar monic_var, lpvar zero_var);
void propagate_monic_with_non_fixed(lpvar monic_var, const svector<lpvar>& vars, lpvar non_fixed, const rational& k);
void propagate_monic_non_fixed_with_lemma(lpvar monic_var, const svector<lpvar>& vars, lpvar non_fixed, const rational& k);
void propagate_monic_with_all_fixed(lpvar monic_var, const svector<lpvar>& vars, const rational& k);
void add_lower_bound_monic(lpvar j, const lp::mpq& v, bool is_strict, std::function<u_dependency*()> explain_dep);