class_docstr: A class to implement some FFT smoothers for Image objects.
  By default, this does a Gaussian kernel smooth. More choices
  would be better!
class_docstr_tok: ["A","class","to","implement","some","FFT","smoothers","for","Image","objects",".","By","default",",","this","does","a","Gaussian","kernel","smooth",".","More","choices","would","be","better","!"]
code: def _presmooth(self, indata):
      slices = [
          slice(0, self.bshape[i], 1) for i in range(len(self.shape))
      ]
      _buffer = np.zeros(self.shape)
      _buffer[tuple(slices)] = indata
      return fft.rfftn(_buffer)
  
file_path: nipy/nipy/algorithms/kernel_smooth.py
imports: import gc
  import numpy
  import numpy.linalg
  from numpy import fft
  from nipy.core.api import AffineTransform, Image
  from nipy.core.reference.coordinate_map import product
  from nipy.utils import seq_prod
label_desc: Use image node_id 6 for calling the LinearFilter obj's underlying member method code with example usage: obj._presmooth(indata) and returns: fft