IVector ode_solver::extract_invariants() {
map<Enode*, pair<double, double>> inv_map;
for (auto inv : m_invs) {
Enode * p = inv->getCdr()->getCdr()->getCdr()->getCdr()->getCar();
Enode * op = p->getCar();
bool pos = true;
// Handle Negation
if (op->getId() == ENODE_ID_NOT) {
p = p->getCdr()->getCar();
op = p->getCar();
pos = false;
}
switch (op->getId()) {
case ENODE_ID_GEQ:
case ENODE_ID_GT:
// Handle >= & >
pos = !pos;
case ENODE_ID_LEQ:
case ENODE_ID_LT: {
// Handle <= & <
Enode * lhs = pos ? p->getCdr()->getCar() : p->getCdr()->getCdr()->getCar();
Enode * rhs = pos ? p->getCdr()->getCdr()->getCar() : p->getCdr()->getCar();
if (lhs->isVar() && rhs->isConstant()) {
if (inv_map.find(lhs) != inv_map.end()) {
inv_map[lhs].second = rhs->getValue();
} else {
inv_map.emplace(lhs, make_pair(lhs->getLowerBound(), rhs->getValue()));
}
} else if (lhs->isConstant() && rhs->isVar()) {
if (inv_map.find(rhs) != inv_map.end()) {
inv_map[rhs].first = lhs->getValue();
} else {
inv_map.emplace(rhs, make_pair(lhs->getValue(), rhs->getUpperBound()));
}
} else {
cerr << "ode_solver::extract_invariant: error:" << p << endl;
}
}
break;
default:
cerr << "ode_solver::extract_invariant: error" << p << endl;
}
}
IVector ret (m_t_vars.size());
unsigned i = 0;
for (auto const & m_t_var : m_t_vars) {
if (inv_map.find(m_t_var) != inv_map.end()) {
auto inv = interval(inv_map[m_t_var].first, inv_map[m_t_var].second);
DREAL_LOG_INFO << "Invariant extracted from " << m_t_var << " = " << inv;
ret[i++] = inv;
} else {
auto inv = interval(m_t_var->getLowerBound(), m_t_var->getUpperBound());
DREAL_LOG_INFO << "Default Invariant set for " << m_t_var << " = " << inv;
ret[i++] = inv;
}
}
return ret;
}
dreal_expr dreal_get_value(dreal_context c, dreal_expr v) {
assert(c);
assert(v);
OpenSMTContext * c_ = static_cast<OpenSMTContext *>(c);
OpenSMTContext & context = *c_;
assert(context.getStatus() == l_True);
Enode * var = static_cast<Enode *>(v);
const Real & value = var->getValue();
Enode * res = context.mkNum(value);
return static_cast<void *>(res);
}
ode_solver::ode_solver(SMTConfig& c,
Egraph & e,
Enode * l_int,
vector<Enode*> invs,
unordered_map<Enode*, int>& enode_to_rp_id) :
m_config(c),
m_egraph(e),
m_int(l_int),
m_invs(invs),
m_enode_to_rp_id(enode_to_rp_id),
m_stepControl(c.nra_ODE_step),
m_time(nullptr) {
// Pick the right flow_map (var |-> ODE) using current mode
m_mode = l_int->getCdr()->getCar()->getValue();
map<string, Enode *> & flow_map = m_egraph.flow_maps[string("flow_") + to_string(m_mode)];
m_time = l_int->getCdr()->getCdr()->getCdr()->getCar();
string time_str = m_time->getCar()->getName(); // i.e. "time_1"
m_step = stoi(time_str.substr(time_str.find_last_of("_") + 1)); // i.e. 1
Enode * var_list = l_int->getCdr()->getCdr()->getCdr()->getCdr();
// Collect _0, _t variables from variable list in integral literal
while (!var_list->isEnil()) {
string name = var_list->getCar()->getCar()->getName();
size_t second_ = name.find_last_of("_");
size_t first_ = name.find_last_of("_", second_ - 1);
string name_prefix, name_postfix;
if (first_ == string::npos) {
name_prefix = name.substr(0, second_);
name_postfix = name.substr(second_);
} else {
name_prefix = name.substr(0, first_);
name_postfix = name.substr(first_);
}
if (flow_map.find(name_prefix) == flow_map.end()) {
cerr << name_prefix << " is not found in flow_map." << endl;
assert(flow_map.find(name_prefix) != flow_map.end());
}
Enode * rhs = flow_map[name_prefix];
stringstream ss;
rhs->print_infix(ss, true, name_postfix);
if (rhs->isConstant() && rhs->getValue() == 0.0) {
// If RHS of ODE == 0.0, we treat it as a parameter in CAPD
m_pars.push_back(var_list->getCar());
m_par_list.push_back(name);
} else {
// Otherwise, we treat it as an ODE variable.
m_0_vars.push_back(var_list->getCar());
m_t_vars.push_back(var_list->getCdr()->getCar());
m_var_list.push_back(name);
m_ode_list.push_back(ss.str());
}
var_list = var_list->getCdr()->getCdr();
}
// join var_list to make diff_var, ode_list to diff_fun_forward
string diff_var = "";
if (!m_var_list.empty()) {
diff_var = "var:" + join(m_var_list, ", ") + ";";
}
string diff_fun_forward = "";
string diff_fun_backward = "";
if (!m_ode_list.empty()) {
diff_fun_forward = "fun:" + join(m_ode_list, ", ") + ";";
diff_fun_backward = "fun: -" + join(m_ode_list, ", -") + ";";
}
// construct diff_sys_forward (string to CAPD)
string diff_par;
if (m_par_list.size() > 0) {
diff_par = "par:" + join(m_par_list, ", ") + ";";
m_diff_sys_forward = diff_par;
m_diff_sys_backward = diff_par;
}
m_diff_sys_forward += diff_var + diff_fun_forward;
m_diff_sys_backward += diff_var + diff_fun_backward;
DREAL_LOG_INFO << "diff_par : " << diff_par;
DREAL_LOG_INFO << "diff_var : " << diff_var;
DREAL_LOG_INFO << "diff_fun_forward : " << diff_fun_forward;
DREAL_LOG_INFO << "diff_fun_backward : " << diff_fun_backward;
DREAL_LOG_INFO << "diff_sys_forward : " << m_diff_sys_forward;
DREAL_LOG_INFO << "diff_sys_backward : " << m_diff_sys_backward;
for (auto ode_str : m_ode_list) {
string const func_str = diff_par + diff_var + "fun:" + ode_str + ";";
m_funcs.push_back(IFunction(func_str));
};
m_inv = extract_invariants();
}