code: def testFlat(self):
      signal = [0.5] * 10
      centroid = sum(range(len(signal))) / float(len(signal))
      relativeCentroid = centroid * (1 / 44100.0)
      energy = sum([x**2 for x in signal])
      strongDecay = sqrt(energy / relativeCentroid)
      self.assertAlmostEqual(StrongDecay()(signal), strongDecay)
  
file_path: essentia/test/src/unittests/temporal/test_strongdecay.py
imports: from essentia_test import *
  from math import sqrt
  from math import fabs
label_desc: Use image node_id 3 for calling the TestStrongDecay obj's underlying member method code with example usage: obj.testFlat() without return types