rename single-letter vars

pymatgen/core/structure.py

@@ -1230,8 +1230,8 @@ def lattice(self) -> Lattice:
     @property
     def density(self) -> float:
         """Returns the density in units of g/cm^3."""
-        m = Mass(self.composition.weight, "amu")
-        return m.to("g") / (self.volume * Length(1, "ang").to("cm") ** 3)
+        mass = Mass(self.composition.weight, "amu")
+        return mass.to("g") / (self.volume * Length(1, "ang").to("cm") ** 3)
 
     @property
     def pbc(self) -> tuple[bool, bool, bool]:
@@ -1258,8 +1258,8 @@ def get_space_group_info(self, symprec=1e-2, angle_tolerance=5.0) -> tuple[str,
         # Import within method needed to avoid cyclic dependency.
         from pymatgen.symmetry.analyzer import SpacegroupAnalyzer
 
-        spga = SpacegroupAnalyzer(self, symprec=symprec, angle_tolerance=angle_tolerance)
-        return spga.get_space_group_symbol(), spga.get_space_group_number()
+        spg_analyzer = SpacegroupAnalyzer(self, symprec=symprec, angle_tolerance=angle_tolerance)
+        return spg_analyzer.get_space_group_symbol(), spg_analyzer.get_space_group_number()
 
     def matches(self, other: IStructure | Structure, anonymous: bool = False, **kwargs) -> bool:
         """Check whether this structure is similar to another structure.
@@ -2308,9 +2308,9 @@ def pbc_coord_intersection(fc1, fc2, tol):
         # reduction.
         # This reduction is O(n^3) so usually is an improvement. Using double
         # the tolerance because both vectors are approximate
-        for g in sorted(grouped_fcoords, key=lambda x: len(x)):
-            for f in g:
-                min_vecs = pbc_coord_intersection(min_vecs, g - f, super_ftol_2)
+        for group in sorted(grouped_fcoords, key=lambda x: len(x)):
+            for frac_coords in group:
+                min_vecs = pbc_coord_intersection(min_vecs, group - frac_coords, super_ftol_2)
 
         def get_hnf(fu):
             """Returns all possible distinct supercell matrices given a
@@ -2321,10 +2321,10 @@ def get_hnf(fu):
             and b first, though unlikely to reduce to O(n^2).
             """
 
-            def factors(n):
-                for i in range(1, n + 1):
-                    if n % i == 0:
-                        yield i
+            def factors(n: int):
+                for idx in range(1, n + 1):
+                    if n % idx == 0:
+                        yield idx
 
             for det in factors(fu):
                 if det == 1:
@@ -2387,8 +2387,8 @@ def factors(n):
                         break
 
                     # check that groups are all cliques
-                    for g in groups:
-                        if not np.all(groups[g][:, g]):
+                    for group in groups:
+                        if not np.all(groups[group][:, group]):
                             valid = False
                             break
                     if not valid:
@@ -3507,7 +3507,7 @@ def from_file(cls, filename):
         installed.
 
         Args:
-            filename (str): The filename to read from.
+            filename (str | Path): The filename to read from.
 
         Returns:
             Molecule
@@ -3530,9 +3530,9 @@ def from_file(cls, filename):
             return cls.from_str(contents, fmt="yaml")
         from pymatgen.io.babel import BabelMolAdaptor
 
-        m = re.search(r"\.(pdb|mol|mdl|sdf|sd|ml2|sy2|mol2|cml|mrv)", filename.lower())
-        if m:
-            new = BabelMolAdaptor.from_file(filename, m.group(1)).pymatgen_mol
+        match = re.search(r"\.(pdb|mol|mdl|sdf|sd|ml2|sy2|mol2|cml|mrv)", filename.lower())
+        if match:
+            new = BabelMolAdaptor.from_file(filename, match.group(1)).pymatgen_mol
             new.__class__ = cls
             return new
         raise ValueError("Cannot determine file type.")

pymatgen/io/cif.py

@@ -487,11 +487,8 @@ def _sanitize_data(self, data):
                 data.data["_atom_site_fract_x"] += new_fract_x
                 data.data["_atom_site_fract_y"] += new_fract_y
                 data.data["_atom_site_fract_z"] += new_fract_z
-        """
-        This fixes inconsistencies in naming of several magCIF tags
-        as a result of magCIF being in widespread use prior to
-        specification being finalized (on advice of Branton Campbell).
-        """
+        # This fixes inconsistencies in naming of several magCIF tags as a result of magCIF
+        # being in widespread use prior to specification being finalized (on advice of Branton Campbell).
         if self.feature_flags["magcif"]:
             # CIF-1 style has all underscores, interim standard
             # had period before magn instead of before the final