docstr: make sure set_triangle_bands fails when list contains a negative
docstr_tok: ["make","sure","set_triangle_bands","fails","when","list","contains","a","negative"]
code: def test_triangle_freqs_with_wrong_negative(self):
      """make sure set_triangle_bands fails when list contains a negative"""
      freq_list = [-10, 0, 80]
      f = filterbank(len(freq_list) - 2, 1024)
      with self.assertRaises(ValueError):
          f.set_triangle_bands(fvec(freq_list), 48000)
  
imports: import numpy
  from numpy.testing import TestCase, assert_equal, assert_almost_equal
  from _tools import assert_warns
  from aubio import fvec, cvec, filterbank, float_type
label_desc: Use image node_id 6 for calling the aubio_filterbank_mel_test_case obj's underlying member method code with example usage: obj.test_triangle_freqs_with_wrong_negative() without return types