code: def test_neg():
      s = Stream.source([3, -4, 6, -7, 2, -6], dtype="float")
  
      s1 = s.neg().rename("s1")
      s2 = (-s).rename("s2")
  
      assert_op([s1, s2], [-3, 4, -6, 7, -2, 6])
  
file_path: tensortrade/tests/tensortrade/unit/feed/api/float/test_operations.py
imports: import pandas
  from tensortrade.feed import Stream
  from tests.utils.ops import assert_op
label_desc: Use image node_id 10 for calling a global function with example usage: test_neg() without return types