added comment

Author: selmanozleyen

src/squidpy/gr/_ligrec.py

@@ -735,7 +735,9 @@ def extractor(res: Sequence[TempResult]) -> TempResult:
     clustering = np.array(data["clusters"].values, dtype=np.int32)
 
     mean = groups.mean().values.T  # (n_genes, n_clusters)
-    mask = groups.apply(lambda c: ((c > 0).astype(int).sum() / len(c)) >= threshold).values.T  # (n_genes, n_clusters)
+    # see https://github.com/scverse/squidpy/pull/991#issuecomment-2888506296
+    # for why we need to cast to int64 here
+    mask = groups.apply(lambda c: ((c > 0).astype(np.int64).sum() / len(c)) >= threshold).values.T  # (n_genes, n_clusters)
 
     # (n_cells, n_genes)
     data = np.array(data[data.columns.difference(["clusters"])].values, dtype=np.float64, order="C")