Avoid generating NaNs in UnwoundPathSum.

Kudos to Jakub Zakrzewski for tracking down the bug.
dmlc · Nov 28, 2018 · 945f6e7 · 945f6e7
1 parent 9c4ff50
commit 945f6e7
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/include/xgboost/tree_model.h b/include/xgboost/tree_model.h
@@ -720,9 +720,11 @@ inline bst_float UnwoundPathSum(const PathElement *unique_path, unsigned unique_
       total += tmp;
       next_one_portion = unique_path[i].pweight - tmp * zero_fraction * ((unique_depth - i)
                          / static_cast<bst_float>(unique_depth + 1));
-    } else {
+    } else if (zero_fraction != 0) {
       total += (unique_path[i].pweight / zero_fraction) / ((unique_depth - i)
                / static_cast<bst_float>(unique_depth + 1));
+    } else {
+      assert(unique_path[i].pweight == 0);
     }
   }
   return total;