code: def testZero(self):
      # zeros should return no onsets
      size = int(5 * sr)
      times, rate = OnsetRate()(zeros(size))
      self.assertEqualVector(times, [])
      self.assertEqual(rate, 0)
  
file_path: essentia/test/src/unittests/rhythm/test_onsetrate.py
imports: from essentia_test import *
  from numpy import random
label_desc: Use image node_id 1 for calling the TestOnsetRate obj's underlying member method code with example usage: obj.testZero() without return types