code: def truncate_transfer(transfer, ncorner=None):
      
      nsamp = transfer.size
      ncorner = ncorner if ncorner else 0
      out = transfer.copy()
      out[0:ncorner] = 0
      out[ncorner:nsamp] *= planck(nsamp-ncorner, nleft=5, nright=5)
      return out
docs: Smoothly zero the edges of a frequency domain transfer function
  
      Parameters
      ----------
      transfer : `numpy.ndarray`
          transfer function to start from, must have at least ten samples
  
      ncorner : `int`, optional
          number of extra samples to zero off at low frequency, default: `None`
  
      Returns
      -------
      out : `numpy.ndarray`
          the smoothly truncated transfer function
  
      Notes
      -----
      By default, the input transfer function will have five samples tapered
      off at the left and right boundaries. If `ncorner` is not `None`, then
      `ncorner` extra samples will be zeroed on the left as a hard highpass
      filter.
  
      See :func:`~gwpy.signal.window.planck` for more information.