Fixes to Potential and Scale

src/py4vasp/_data/structure.py

@@ -291,8 +291,8 @@ def _lattice_vectors(self):
         return self._scale() * lattice_vectors[self._get_steps()]
 
     def _scale(self):
-        if isinstance(self._raw_data.cell.scale, np.float_):
-            return self._raw_data.cell.scale
+        if isinstance(self._raw_data.cell.scale, (float, np.floating)):
+            return raw.VaspData(self._raw_data.cell.scale)
         if not self._raw_data.cell.scale.is_none():
             return self._raw_data.cell.scale[()]
         else:

src/py4vasp/_raw/data.py

@@ -82,7 +82,7 @@ class Cell:
 
     lattice_vectors: VaspData
     "Lattice vectors defining the unit cell."
-    scale: float
+    scale: VaspData = NONE()
     "Global scaling factor applied to all lattice vectors."