Fixed iter of Coordinates after last change

src/mdevaluate/coordinates.py

@@ -218,7 +218,7 @@ class Coordinates:
             self.get_frame.clear_cache()
 
     def __iter__(self):
-        for i in range(len(self))[self._slice]:
+        for i in range(len(self)):
             yield self[i]
 
     @singledispatchmethod
@@ -232,7 +232,7 @@ class Coordinates:
         return sliced
 
     def __len__(self):
-        return len(self.frames)
+        return len(self.frames[self._slice])
 
     def __checksum__(self):
         return checksum(self.frames, self.atom_filter, self._slice, self.mode)