void tilingInterpolation::integer_pruning(box const & old_box, box const & new_box, int i) {
Enode * it;
//TODO what about shared ? should we rather take the projections
if (is_a_var(i)) {
it = make_false();
} else {
assert(is_b_var(i));
it = make_true();
}
if (new_box.get_values()[i].is_empty()) {
//if the new box is empty then we have a leaf
push_partial_interpolant(it);
proof_size += 1;
} else {
//we need to figure out what parts are pruned
auto const fst_value = old_box.get_value(i);
auto const snd_value = new_box.get_value(i);
//pruning on the lower end
if (fst_value.lb() < snd_value.lb()) {
std::tuple<bool,int,double,bool> pivot(false, i, snd_value.lb(), false);
split_stack.push(pivot);
push_partial_interpolant(it);
proof_size += 1;
}
//pruning on the upper end
if (fst_value.ub() > snd_value.ub()) {
std::tuple<bool,int,double,bool> pivot(true, i, snd_value.ub(), false);
split_stack.push(pivot);
push_partial_interpolant(it);
proof_size += 1;
}
}
}
void tilingInterpolation::pruning(box const & old_box, box const & new_box, std::shared_ptr<constraint> cstr) {
Enode * it;
if (is_a_constraint(cstr)) {
it = make_false();
} else if (is_b_constraint(cstr)) {
it = make_true();
} else {
assert(is_bound(cstr));
DREAL_LOG_DEBUG << "pruning, ignoring bound: " << cstr.get();
return;
}
if (new_box.is_empty()) {
//if the new box is empty then we have a leaf
push_partial_interpolant(it);
proof_size += 1;
} else {
//we need to figure out what parts are pruned
int max_var = domain.get_vars().size();
for (int i = 0; i < max_var; i++) {
auto const fst_value = old_box.get_value(i);
auto const snd_value = new_box.get_value(i);
//pruning on the lower end
if (fst_value.lb() < snd_value.lb()) {
std::tuple<bool,int,double,bool> pivot(false, i, snd_value.lb(), false);
split_stack.push(pivot);
push_partial_interpolant(it);
proof_size += 1;
}
//pruning on the upper end
if (fst_value.ub() > snd_value.ub()) {
std::tuple<bool,int,double,bool> pivot(true, i, snd_value.ub(), false);
split_stack.push(pivot);
push_partial_interpolant(it);
proof_size += 1;
}
}
}
}
bool optimizer::improve_naive(box& p) { //note that p is a point not a nontrivial box
Enode * target = NULL; //will pick one target error function
double delta = config.nra_precision;
double max_error = delta;
for (auto f : error_funcs) {
//evaluate f on p
double c = std::fabs(eval_enode_term(f,p));
cerr << "for f = " << f << ", the error evaluates to " << c << endl;
if (c > max_error) {
max_error = c;
target = f;
}
}
if (max_error<=delta) {
cerr << "error already minimized" << endl;
return false;
}
cerr << "max_error is: " << max_error << ", happening on function " << target << endl;
//otherwise, move on each dimension based on the gradient of f
Enode * ptarget = plainf[target]; //use the simplified form for computing gradients
map<Enode*, double> new_values;
unordered_set<Enode*> vars = ptarget->get_vars();
for (auto v : vars) {
Enode * gradient_v = egraph.mkDeriv(ptarget,v);
double p_v = p.get_value(v).lb();
double grad = eval_enode_term(gradient_v,p);
//take a newton step on the dimention
cerr << "exploring the domain:\n" << domain << endl;
double length = domain.get_value(v).ub() - domain.get_value(v).lb();
double step = ((p_v-domain.get_value(v).lb())/(length+delta))*(domain.get_value(v).ub()-p_v);
cerr << "taking a step of size: " << step << endl;
cerr << "at gradient " << grad << endl;
double newv = p_v - step*grad;
cerr << "making a move on " << v << " by " << newv << endl;
new_values.emplace(v,newv);
}
//TODO: collect the box that it has been through
//if value interval has no zero, push to the learned boxes; the new point is the improved point
//if value interval has zero, push that box to the top!
for (auto v : vars) {
//change the value in p using the new point
p.set_value(v,new_values[v],new_values[v]); //lower and upper bounds are the same
}
cerr << "the new point is:\n" << p << endl;
return true;
}
double eval_enode_term(Enode * const e, box const & b) {
if (e->isVar()) {
return b.get_value(e).lb();
} else if (e->isConstant()) {
double const v = e->getValue();
return v;
} else if (e->isSymb()) {
throw runtime_error("eval_enode: Symb");
} else if (e->isNumb()) {
throw runtime_error("eval_enode: Numb");
} else if (e->isTerm()) {
assert(e->getArity() >= 1);
enodeid_t id = e->getCar()->getId();
double ret = 0.0;
Enode * tmp = e;
switch (id) {
case ENODE_ID_PLUS:
ret = eval_enode_term(tmp->get1st(), b);
tmp = tmp->getCdr()->getCdr(); // e is pointing to the 2nd arg
while (!tmp->isEnil()) {
ret = ret + eval_enode_term(tmp->getCar(), b);
tmp = tmp->getCdr();
}
return ret;
case ENODE_ID_MINUS:
ret = eval_enode_term(tmp->get1st(), b);
tmp = tmp->getCdr()->getCdr(); // e is pointing to the 2nd arg
while (!tmp->isEnil()) {
ret = ret - eval_enode_term(tmp->getCar(), b);
tmp = tmp->getCdr();
}
return ret;
case ENODE_ID_UMINUS:
ret = eval_enode_term(tmp->get1st(), b);
assert(tmp->getArity() == 1);
return (- ret);
case ENODE_ID_TIMES:
ret = eval_enode_term(tmp->get1st(), b);
tmp = tmp->getCdr()->getCdr(); // e is pointing to the 2nd arg
while (!tmp->isEnil()) {
ret = ret * eval_enode_term(tmp->getCar(), b);
tmp = tmp->getCdr();
}
return ret;
case ENODE_ID_DIV:
ret = eval_enode_term(tmp->get1st(), b);
tmp = tmp->getCdr()->getCdr(); // e is pointing to the 2nd arg
while (!tmp->isEnil()) {
ret = ret / eval_enode_term(tmp->getCar(), b);
tmp = tmp->getCdr();
}
return ret;
case ENODE_ID_ACOS:
assert(e->getArity() == 1);
return acos(eval_enode_term(e->get1st(), b));
case ENODE_ID_ASIN:
assert(e->getArity() == 1);
return asin(eval_enode_term(e->get1st(), b));
case ENODE_ID_ATAN:
assert(e->getArity() == 1);
return atan(eval_enode_term(e->get1st(), b));
case ENODE_ID_ATAN2:
assert(e->getArity() == 2);
return atan2(eval_enode_term(e->get1st(), b),
eval_enode_term(e->get2nd(), b));
case ENODE_ID_MIN:
assert(e->getArity() == 2);
return fmin(eval_enode_term(e->get1st(), b),
eval_enode_term(e->get2nd(), b));
case ENODE_ID_MAX:
assert(e->getArity() == 2);
return fmax(eval_enode_term(e->get1st(), b),
eval_enode_term(e->get2nd(), b));
case ENODE_ID_MATAN:
assert(e->getArity() == 1);
throw runtime_error("eval_enode: MATAN");
case ENODE_ID_SAFESQRT:
assert(e->getArity() == 1);
throw runtime_error("eval_enode: SAFESQRT");
case ENODE_ID_SQRT:
assert(e->getArity() == 1);
return sqrt(eval_enode_term(e->get1st(), b));
case ENODE_ID_EXP:
assert(e->getArity() == 1);
return exp(eval_enode_term(e->get1st(), b));
case ENODE_ID_LOG:
assert(e->getArity() == 1);
return log(eval_enode_term(e->get1st(), b));
case ENODE_ID_POW:
assert(e->getArity() == 2);
return pow(eval_enode_term(e->get1st(), b),
eval_enode_term(e->get2nd(), b));
case ENODE_ID_ABS:
assert(e->getArity() == 1);
return fabs(eval_enode_term(e->get1st(), b));
case ENODE_ID_SIN:
assert(e->getArity() == 1);
return sin(eval_enode_term(e->get1st(), b));
case ENODE_ID_COS:
assert(e->getArity() == 1);
return cos(eval_enode_term(e->get1st(), b));
case ENODE_ID_TAN:
assert(e->getArity() == 1);
return tan(eval_enode_term(e->get1st(), b));
case ENODE_ID_SINH:
assert(e->getArity() == 1);
return sinh(eval_enode_term(e->get1st(), b));
case ENODE_ID_COSH:
assert(e->getArity() == 1);
return cosh(eval_enode_term(e->get1st(), b));
case ENODE_ID_TANH:
assert(e->getArity() == 1);
return tanh(eval_enode_term(e->get1st(), b));
default:
throw runtime_error("eval_enode: Unknown Term");
}
} else if (e->isList()) {
throw runtime_error("eval_enode: List");
} else if (e->isDef()) {
throw runtime_error("eval_enode: Def");
} else if (e->isEnil()) {
throw runtime_error("eval_enode: Nil");
} else {
throw runtime_error("eval_enode: unknown case");
}
throw runtime_error("Not implemented yet: eval_enode");
}
