code: def build_sinusoid(self, length, freq, samplerate):
      return sin(
          2.0
          * pi
          * arange(length).astype(float_type)
          * freq
          / samplerate
      )
  
file_path: aubio/python/tests/test_pitch.py
imports: from numpy.testing import TestCase, assert_equal
  from numpy import sin, arange, mean, median, isnan, pi
  from aubio import fvec, pitch, freqtomidi, float_type
label_desc: Use image node_id 2 for calling the aubio_pitch_Sinusoid obj's underlying member method code with example usage: obj.build_sinusoid(length, freq, samplerate) and returns: sin