add option to get bwdf for specific label and none normalization

src/lobsterpy/featurize/batch.py

@@ -862,7 +862,7 @@ class BatchIcoxxlistFeaturizer:
     def __init__(
         self,
         path_to_lobster_calcs: str | Path,
-        normalization: Literal["formula_units", "area"] = "formula_units",
+        normalization: Literal["formula_units", "area", "none"] = "formula_units",
         bin_width: float = 0.02,
         max_length: float = 6.0,
         min_length: float = 0.0,

src/lobsterpy/featurize/core.py

@@ -1179,7 +1179,7 @@ def __init__(
         bin_width: float = 0.02,
         max_length: float = 6.0,
         min_length: float = 0.0,
-        normalization: Literal["formula_units", "area"] = "formula_units",
+        normalization: Literal["formula_units", "area", "none"] = "formula_units",
         are_cobis: bool = False,
         are_coops: bool = False,
     ):
@@ -1306,7 +1306,7 @@ def calc_bwdf(self):
                 if self.normalization == "area":
                     total_area = np.sum(np.abs(bwdf_atom_pair[atom_pair]["icoxx_binned"]) * self.bin_width)
                     bwdf_atom_pair[atom_pair]["icoxx_binned"] = bwdf_atom_pair[atom_pair]["icoxx_binned"] / total_area
-                else:
+                elif self.normalization == "formula_units":
                     formula_units = self.structure.composition.get_reduced_formula_and_factor()[-1]
                     bwdf_atom_pair[atom_pair]["icoxx_binned"] = (
                         bwdf_atom_pair[atom_pair]["icoxx_binned"] / formula_units
@@ -1412,12 +1412,60 @@ def calc_site_bwdf(self, site_index: int) -> dict:
         if self.normalization == "area":
             total_area = np.sum(np.abs(site_bwdf["icoxx_binned"]) * self.bin_width)
             site_bwdf["icoxx_binned"] = site_bwdf["icoxx_binned"] / total_area
-        else:
+        elif self.normalization == "formula_units":
             formula_units = self.structure.composition.get_reduced_formula_and_factor()[-1]
             site_bwdf["icoxx_binned"] = site_bwdf["icoxx_binned"] / formula_units
 
         return site_bwdf
 
+    def calc_label_bwdf(self, bond_label: str) -> dict:
+        """
+        Compute BWDF from ICOXXLIST.lobster data for a bond label.
+
+        Args:
+            bond_label: bond label for which BWDF needs to be computed
+
+        Returns:
+            BWDF for a bond label as a dictionary
+        """
+        index = self.icoxxlist.icohpcollection._list_labels.index(bond_label)
+        bond_length = self.icoxxlist.icohpcollection._list_length[index]
+        atom1 = self.icoxxlist.icohpcollection._list_atom1[index]
+        atom2 = self.icoxxlist.icohpcollection._list_atom2[index]
+        icoxx = sum(self.icoxxlist.icohpcollection._list_icohp[index].values())
+        trans = self.icoxxlist.icohpcollection._list_translation[index]
+
+        # Complete data
+        complete_data = [(sorted([atom1, atom2]), bond_length, trans, icoxx)]
+
+        # Calculate number of bins
+        n_bins = int(np.ceil((self.max_length - self.min_length) / self.bin_width))
+
+        # Get bin edges and centers
+        bin_edges = np.round(np.linspace(self.min_length, self.max_length, n_bins), 5)
+        bin_centers = bin_edges[:-1] + self.bin_width / 2
+
+        # Initialize dictionary for storing binned data by atom pair
+        label_bwdf = {"icoxx_binned": np.zeros(bin_centers.shape)}
+
+        for interactions in complete_data:
+            for ii, l1, l2 in zip(range(len(bin_centers)), bin_edges[:-1], bin_edges[1:]):
+                if interactions[1] >= l1 and interactions[1] < l2:
+                    label_bwdf["icoxx_binned"][ii] += interactions[3]  # sum icoxx values in the bin
+
+        label_bwdf["centers"] = bin_centers
+        label_bwdf["edges"] = bin_edges
+        label_bwdf["bin_width"] = self.bin_width
+
+        if self.normalization == "area":
+            total_area = np.sum(np.abs(label_bwdf["icoxx_binned"]) * self.bin_width)
+            label_bwdf["icoxx_binned"] = label_bwdf["icoxx_binned"] / total_area
+        elif self.normalization == "formula_units":
+            formula_units = self.structure.composition.get_reduced_formula_and_factor()[-1]
+            label_bwdf["icoxx_binned"] = label_bwdf["icoxx_binned"] / formula_units
+
+        return label_bwdf
+
     @staticmethod
     def _get_features_col_names(bwdf: dict) -> list[str]:
         """