code: def frequency_bins(header):
    '''
    Returnes the frequency-axis lower bin edge values for the spectrogram. 
    '''
  
    center_frequency = 1.0e6*header['rf_center_frequency']
    if header["number_of_subbands"] > 1:
      center_frequency += header["subband_spacing_hz"]*(header["number_of_subbands"]/2.0 - 0.5)
  
    return np.fft.fftshift(\
      np.fft.fftfreq( int(header["number_of_subbands"] * constants.bins_per_half_frame*(1.0 - header['over_sampling'])), \
        1.0/(header["number_of_subbands"]*header["subband_spacing_hz"])) + center_frequency
      f frequency_bins(header):
    '''
    Returnes the frequency-axis lower bin edge values for the spectrogram. 
    '''
  
    center_frequency = 1.0e6*header['rf_center_frequency']
    if header["number_of_subbands"] > 1:
      center_frequency += header["subband_spacing_hz"]*(header["number_of_subbands"]/2.0 - 0.5)
  
    return np.fft.fftshift(\
      np.fft.fftfreq( int(header["number_of_subbands"] * constants.bins_per_half_frame*(1.0 - header['over_sampling'])), \
        1.0/(header["number_of_subbands"]*header["subband_spacing_hz"])) + center_frequency
      )
docs: Returnes the frequency-axis lower bin edge values for the spectrogram.