class_docstr: Unit test class for filters
  TODO: Docstring
docstr: Unit test sign contributions 2
docstr_tok: ["Unit","test","sign","contributions","2"]
code: def test_sign_contributions_2(self):
      """
      Unit test sign contributions 2
      """
      dataframe = pd.DataFrame(
          {"val1": [1, -1], "val2": [-2, -2], "val3": [0.5, -2]}
      )
      output = sign_contributions(dataframe, positive=False)
      expected = pd.DataFrame(
          {
              "val1": [False, True],
              "val2": [True, True],
              "val3": [False, True],
          }
      )
      pd.testing.assert_frame_equal(output, expected)
  
imports: import unittest
  import numpy
  import pandas
  from shapash.manipulation.filters import cutoff_contributions, cutoff_contributions_old
  from shapash.manipulation.filters import cap_contributions
  from shapash.manipulation.filters import hide_contributions
  from shapash.manipulation.filters import sign_contributions
  from shapash.manipulation.filters import combine_masks
label_desc: Use image node_id 6 for calling the TestFilter obj's underlying member method code with example usage: obj.test_sign_contributions_2() without return types