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fix infinite loop issue in def::operator+, other issues remain though for #6404

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The example from #6404 results in an incorrect result. It uses integer division on private variables where MBQI support is new and not tested for substitutions.
This commit is contained in:
Nikolaj Bjorner 2022-10-18 14:52:30 -07:00
parent cdfab8cb13
commit eaf52f4c32
2 changed files with 31 additions and 4 deletions
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34
src/math/simplex/model_based_opt.cpp
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@ -98,11 +98,13 @@ namespace opt {
}
else if (v1 < v2) {
vs.push_back(vs1[i]);
vs.back().m_coeff *= c1;
vs.back().m_coeff *= c1;
++i;
}
else {
vs.push_back(vs2[j]);
vs.back().m_coeff *= c2;
vs.back().m_coeff *= c2;
++j;
}
}
result.m_div = c1*m_div;
@ -111,6 +113,26 @@ namespace opt {
return result;
}
model_based_opt::def model_based_opt::def::substitute(unsigned v, def const& other) const {
def result;
vector<var> const& vs1 = m_vars;
vector<var> const& vs2 = other.m_vars;
rational coeff(0);
for (auto const& [id, c] : vs1) {
if (id == v) {
coeff = c;
break;
}
}
if (coeff == 0) {
return *this;
}
NOT_IMPLEMENTED_YET();
result.normalize();
return result;
}
model_based_opt::def model_based_opt::def::operator/(rational const& r) const {
def result(*this);
result.m_div *= r;
@ -1418,13 +1440,17 @@ namespace opt {
project(v, false);
// project internal variables.
def y_def = project(y, compute_def);
def z_def = project(z, compute_def);
def y_def = project(y, compute_def); // may depend on z
if (compute_def) {
result = (y_def * K) + z_def;
m_var2value[x] = eval(result);
TRACE("opt", tout << y << " := " << y_def << "\n";
tout << z << " := " << z_def << "\n";
tout << x << " := " << result << "\n");
}
TRACE("opt", display(tout << "solve_div done v" << x << "\n"));
return result;

1
src/math/simplex/model_based_opt.h
View file

@ -86,6 +86,7 @@ namespace opt {
def operator/(rational const& n) const;
def operator*(rational const& n) const;
def operator+(rational const& n) const;
def substitute(unsigned v, def const& other) const;
void normalize();
};