[Code scan] Fix LDOS valence-band slicing and z-scan indexing

[njzjz]

This issue comes from a Codex global repository scan.

Problem

LDOS.__init__() computes self.n_valbands with /, so it stores a float:

dftio/dftio/calc/ldos.py

Lines 49 to 50 in c9d128f

	if z_valence is not None:
	self.n_valbands = sum([z_valence[atomic_numbers_r[i]] for i in self.atomic_numbers]) / self.nspin

LDOS.get() later assigns that float to n and uses it as a slice bound:

dftio/dftio/calc/ldos.py

Lines 97 to 105 in c9d128f

	if self.n_valbands:
	assert n >= self.n_valbands, f"Number of bands must be at least {self.n_valbands}"
	n = self.n_valbands
	else:
	print("Warning: Number of valence bands not provided. All input coeff and eigenvalues are considered corresponding to valence bands.")
	assert m >= n
	coefficients = coefficients[:,:n]
	eigenvalues = eigenvalues[:,:n]

This raises TypeError: slice indices must be integers when z_valence is provided.

LDOS.scan() also has a left-branch off-by-one: ldos_wbias_diff has length nz - 1, but the loop indexes it up to i == nz - 1:

dftio/dftio/calc/ldos.py

Lines 205 to 207 in c9d128f

	for i in range(1,nz):
	mask = torch.logical_or(mask, ldos_wbias_diff[:,:,i] < 0)
	ldos_wbias[:,:,i][mask] = 100

Suggested fix

Validate valence-band divisibility and store an integer band count. In scan(), iterate only over valid diff indices and explicitly write to the corresponding shifted z-plane.