make dependencies optional

Author: naik-aakash

src/lobsterpy/cli.py

@@ -7,6 +7,7 @@
 
 import argparse
 import json
+import warnings
 from math import log, sqrt
 from pathlib import Path
 
@@ -19,7 +20,20 @@
 
 from lobsterpy.cohp.analyze import Analysis
 from lobsterpy.cohp.describe import Description
-from lobsterpy.featurize.core import FeaturizeIcoxxlist
+
+try:
+    from lobsterpy.featurize.core import FeaturizeIcoxxlist
+
+except ModuleNotFoundError:
+    FeaturizeIcoxxlist = None
+    warnings.warn(
+        "plot-bwdf action is not available as the "
+        "dependencies needed for the featurize module is not installed. "
+        "To enable this action reinstall the package with "
+        "`pip install lobsterpy[featurizer]` command.",
+        stacklevel=1,
+    )
+
 from lobsterpy.featurize.utils import get_file_paths
 from lobsterpy.plotting import (
     BWDFPlotter,

src/lobsterpy/featurize/utils.py

@@ -10,7 +10,7 @@
 from warnings import warn
 
 import numpy as np
-from mendeleev import element
+from monty.dev import requires
 from monty.os.path import zpath
 
 POSCAR_WARNING = (
@@ -130,6 +130,9 @@ def get_structure_path(lobster_path: Path) -> Path:
     raise Exception
 
 
+@requires(
+    "mendeleev", "get_reduced_mass requires mendeleev. Reinstall package with `pip install lobsterpy[featurizer]`."
+)
 def get_reduced_mass(atom_pair: list[str]) -> float:
     """
     Compute reduced mass between a pair of atoms.
@@ -138,11 +141,17 @@ def get_reduced_mass(atom_pair: list[str]) -> float:
 
     :return: reduced mass
     """
+    from mendeleev import element
+
     atom1 = element(atom_pair[0])
     atom2 = element(atom_pair[1])
     return (atom1.atomic_weight * atom2.atomic_weight) / (atom1.atomic_weight + atom2.atomic_weight)
 
 
+@requires(
+    "mendeleev",
+    "get_electronegativities requires mendeleev. Reinstall package with `pip install lobsterpy[featurizer]`.",
+)
 def get_electronegativities(atom_pair: list[str]) -> list[float]:
     """
     Get Allen electronegativities for a pair of atoms.
@@ -151,6 +160,8 @@ def get_electronegativities(atom_pair: list[str]) -> list[float]:
 
     :return: list of Allen electronegativities
     """
+    from mendeleev import element
+
     atom1 = element(atom_pair[0])
     atom2 = element(atom_pair[1])
     return [atom1.electronegativity_allen(), atom2.electronegativity_allen()]