diff --git a/modules/mol/alg/pymod/ligand_scoring.py b/modules/mol/alg/pymod/ligand_scoring.py
index d52fbc60c5f4c86465deacdd1cec71731368df06..5739ffd47d3cc120b1c585b392e94ca96f7bed5d 100644
--- a/modules/mol/alg/pymod/ligand_scoring.py
+++ b/modules/mol/alg/pymod/ligand_scoring.py
@@ -588,6 +588,9 @@ class LigandScorer:
 
         Target ligands are in rows, model ligands in columns.
 
+        Infinite values indicate that no RMSD could be computed (i.e. different
+        ligands).
+
         :rtype: :class:`~numpy.ndarray`
         """
         if self._rmsd_full_matrix is None:
@@ -608,6 +611,9 @@ class LigandScorer:
 
         Target ligands are in rows, model ligands in columns.
 
+        A value of 0 indicate that no lDDT-PLI could be computed (i.e. different
+        ligands).
+
         :rtype: :class:`~numpy.ndarray`
         """
         if self._lddt_pli_full_matrix is None: