Only use length of array instead of whole array

src/py4vasp/data/dos.py

@@ -147,5 +147,5 @@ def _merge_labels(self, labels):
 
  def _read_element(self, index):
  sum_dos = lambda dos, i: dos + self._partial_dos[i]
- zero_dos = np.zeros_like(self._energies[:])
+ zero_dos = np.zeros(len(self._energies))
  return functools.reduce(sum_dos, itertools.product(*index), zero_dos)