Fixes case where multiple monomers have the same MW

Fixes #12
NREL · Aug 6, 2024 · 1854f77 · 1854f77
1 parent 647bd55
commit 1854f77
Showing 1 changed file with 7 additions and 4 deletions.
diff --git a/m2p/polymaker.py b/m2p/polymaker.py
@@ -177,11 +177,14 @@ def get_monomers(
  monomers == None
  # Sort by MW
  if sort_by_mw == True:
- dict_mw_smile = {
- Descriptors.ExactMolWt(Chem.MolFromSmiles(Chem.CanonSmiles(s))): s
+ # use a list of tuples instead of a dicitonary
+ # in case there are monomers with the same molecular weight
+ list_mw_smile = [
+ (Descriptors.ExactMolWt(Chem.MolFromSmiles(Chem.CanonSmiles(s))), s)
  for s in monomers
- }
- monomers = tuple(dict_mw_smile[k] for k in sorted(dict_mw_smile))
+ ]
+ monomers = tuple(s for mw, s in sorted(list_mw_smile, 
+ key=lambda x: x[0]))
 
  return monomers