Raise ValueError when sampling an empty Domain
[linpy.git] / pypol / domains.py
index dd39220..1ffed45 100644 (file)
@@ -144,7 +144,7 @@ class Domain:
         islset = libisl.isl_set_remove_redundancies(islset)
         return self._fromislset(islset, self.symbols)
 
-    def polyhedral_hull(self):
+    def aspolyhedron(self):
         # several types of hull are available
         # polyhedral seems to be the more appropriate, to be checked
         from .polyhedra import Polyhedron
@@ -168,12 +168,19 @@ class Domain:
         return Domain._fromislset(islset, dims)
 
     def sample(self):
-        from .polyhedra import Polyhedron
         islset = self._toislset(self.polyhedra, self.symbols)
-        islbset = libisl.isl_set_sample(islset)
-        # next instruction should NOT be required
-        islbset = libisl.isl_basic_set_finalize(islbset)
-        return Polyhedron._fromislbasicset(islbset, self.symbols)
+        islpoint = libisl.isl_set_sample_point(islset)
+        if bool(libisl.isl_point_is_void(islpoint)):
+            libisl.isl_point_free(islpoint)
+            raise ValueError('domain must be non-empty')
+        point = {}
+        for index, symbol in enumerate(self.symbols):
+            coordinate = libisl.isl_point_get_coordinate_val(islpoint,
+                libisl.isl_dim_set, index)
+            coordinate = islhelper.isl_val_to_int(coordinate)
+            point[symbol] = coordinate
+        libisl.isl_point_free(islpoint)
+        return point
 
     def intersection(self, *others):
         if len(others) == 0: