code: def testRegression(self):
      input = readVector(join(filedir(), "rolloff", "input.txt"))
      expected = readVector(join(filedir(), "rolloff", "output.txt"))[0]
  
      result = RollOff(cutoff=0.85)(input)
      self.assertAlmostEqual(result, expected)
  
file_path: essentia/test/src/unittests/spectral/test_rolloff.py
imports: from essentia_test import *
label_desc: Use image node_id 9 for calling the TestRollOff obj's underlying member method code with example usage: obj.testRegression() without return types