code: def _merge_pos_arr(s: pd.Series):
      arr_1 = s["sample_pos"]
      arr_2 = s["host_sample_pos"]
      arr_1 = np.array(arr_1)
      arr_2 = np.array(arr_2)
      assert len(arr_1) == len(arr_2)
      merge_rs = np.copy(arr_1)
      already_on_leaf = arr_1 < 0
      on_leaf = arr_2 < 0
      updated = ~already_on_leaf & (on_leaf | (arr_2 > arr_1))
      merge_rs[updated] = arr_2[updated]
      return [merge_rs]
  
file_path: FATE/python/fate/ml/ensemble/algo/secureboost/common/predict.py
imports: import pandas
  import numpy
  from typing import List
  from fate.arch import Context
  from fate.arch.dataframe import DataFrame
  import copy
  from fate.ml.ensemble.learner.decision_tree.tree_core.decision_tree import DecisionTree, _make_decision, Node
  import functools
  from logging import getLogger
label_desc: Use image node_id 7 for calling a global function with example usage: _merge_pos_arr(s) and returns: list