From 147cb854b0f1ee618151cf45391725dcc63ad9aa Mon Sep 17 00:00:00 2001
From: "Haoyu (Daniel)" <yanghaoyu97@outlook.com>
Date: Sat, 13 Apr 2024 21:37:04 +0800
Subject: [PATCH] fix io.vasp

---
 pymatgen/io/vasp/inputs.py  | 16 ++++++++++------
 pymatgen/io/vasp/outputs.py |  8 ++++++++
 2 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/pymatgen/io/vasp/inputs.py b/pymatgen/io/vasp/inputs.py
index 66cd67cabb8..4a3f54c1c00 100644
--- a/pymatgen/io/vasp/inputs.py
+++ b/pymatgen/io/vasp/inputs.py
@@ -328,6 +328,7 @@ def from_str(cls, data, default_names=None, read_velocities=True) -> Self:
             lattice *= scale
 
         vasp5_symbols = False
+        atomic_symbols = []
         try:
             n_atoms = [int(i) for i in lines[5].split()]
             ipos = 6
@@ -362,7 +363,7 @@ def from_str(cls, data, default_names=None, read_velocities=True) -> Self:
             iline_natoms_start = 5 + n_lines_symbols
             for iline_natoms in range(iline_natoms_start, iline_natoms_start + n_lines_symbols):
                 n_atoms.extend([int(i) for i in lines[iline_natoms].split()])
-            atomic_symbols = []
+
             for i, nat in enumerate(n_atoms):
                 atomic_symbols.extend([symbols[i]] * nat)
             ipos = 5 + 2 * n_lines_symbols
@@ -383,11 +384,12 @@ def from_str(cls, data, default_names=None, read_velocities=True) -> Self:
         # them. This is in line with VASP's parsing order that the POTCAR
         # specified is the default used.
         if default_names:
-            with contextlib.suppress(IndexError):
-                atomic_symbols = []
+            try:
                 for i, nat in enumerate(n_atoms):
                     atomic_symbols.extend([default_names[i]] * nat)
                 vasp5_symbols = True
+            except IndexError:
+                pass
 
         if not vasp5_symbols:
             ind = 6 if has_selective_dynamics else 3
@@ -1389,8 +1391,11 @@ def from_str(cls, string: str) -> Self:
 
             kpts_shift: tuple[float, float, float] = (0, 0, 0)
             if len(lines) > 4 and coord_pattern.match(lines[4]):
-                with contextlib.suppress(ValueError):
+                try:
                     _kpts_shift = tuple(float(i) for i in lines[4].split())
+                except ValueError:
+                    _kpts_shift = (0, 0, 0)
+
                 if len(_kpts_shift) == 3:
                     kpts_shift = _kpts_shift
 
@@ -1400,8 +1405,7 @@ def from_str(cls, string: str) -> Self:
         if num_kpts <= 0:
             _style = cls.supported_modes.Cartesian if style in "ck" else cls.supported_modes.Reciprocal
             _kpts_shift = tuple(float(i) for i in lines[6].split())
-            if len(_kpts_shift) == 3:
-                kpts_shift = _kpts_shift
+            kpts_shift = _kpts_shift if len(_kpts_shift) == 3 else (0, 0, 0)
 
             return cls(
                 comment=comment,
diff --git a/pymatgen/io/vasp/outputs.py b/pymatgen/io/vasp/outputs.py
index 1444987e98a..22d966d685e 100644
--- a/pymatgen/io/vasp/outputs.py
+++ b/pymatgen/io/vasp/outputs.py
@@ -3776,7 +3776,15 @@ def __init__(self, filename):
             current_band = 0
             done = False
             spin = Spin.down
+
             weights = None
+            n_kpoints = None
+            n_bands = None
+            n_ions = None
+            weights = []
+            headers = None
+            data = None
+            phase_factors = None
 
             for line in file_handle:
                 line = line.strip()