code: def testZeroSpectrum(self):
      # Inputting zeros should return zero. Try with different sizes.
      size = 1024
      while size >= 256:
          self.assertEqualVector(MelBands()(zeros(size)), zeros(24))
          size = size // 2
  
file_path: essentia/test/src/unittests/spectral/test_melbands.py
imports: from essentia_test import *
  import numpy
label_desc: Use image node_id 3 for calling the TestMelBands obj's underlying member method code with example usage: obj.testZeroSpectrum() without return types