reimplement + test implicit validity domain function

stl/utils.py

@@ -42,12 +42,15 @@ def f_neg_or_canonical_form(phi: STL) -> STL:
 
 
 def _lineq_lipschitz(lineq):
-    return sum(map(abs, bind(lineq).Each().terms.Each().coeff.collect()))
+    return sum(map(abs, bind(lineq).terms.Each().coeff.collect()))
 
 
 def linear_stl_lipschitz(phi):
     """Infinity norm lipschitz bound of linear inequality predicate."""
-    return float(max(map(_lineq_lipschitz, phi.lineqs)))
+    if any(isinstance(psi, (AtomicPred, _Top, _Bot)) for psi in phi.walk()):
+        return float('inf')
+
+    return float(max(map(_lineq_lipschitz, phi.lineqs), default=float('inf')))
 
 
 op_lookup = {
@@ -59,11 +62,6 @@ op_lookup = {
 }
 
 
-def get_times(x):
-    times = set.union(*({t for t, _ in v.items()} for v in x.values()))
-    return sorted(times)
-
-
 def const_trace(x, start=0):
     return traces.TimeSeries([(start, x)], domain=traces.Domain(start, oo))
 
@@ -87,6 +85,19 @@ def eval_lineqs(phi, x):
     return {lineq: eval_lineq(lineq, x, domain) for lineq in lineqs}
 
 
+def implicit_validity_domain(phi, trace):
+    params = {ap.name for ap in phi.params}
+    order = tuple(params)
+
+    def vec_to_dict(theta):
+        return {k: v for k, v in zip(order, theta)}
+
+    def oracle(theta):
+        return stl.pointwise_sat(phi.set_params(vec_to_dict(theta)))(trace, 0)
+
+    return oracle, order
+
+
 # EDSL