--- a/scripts/signal/fftfilt.m
+++ b/scripts/signal/fftfilt.m
@@ -1,39 +1,40 @@
-# Copyright (C) 1996 John W. Eaton
-# 
-# This file is part of Octave.
-# 
-# Octave is free software; you can redistribute it and/or modify it
-# under the terms of the GNU General Public License as published by the
-# Free Software Foundation; either version 2, or (at your option) any
-# later version.
-# 
-# Octave is distributed in the hope that it will be useful, but WITHOUT
-# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
-# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
-# for more details.
-# 
-# You should have received a copy of the GNU General Public License
-# along with Octave; see the file COPYING.  If not, write to the Free
-# Software Foundation, 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+### Copyright (C) 1996 John W. Eaton
+###
+### This file is part of Octave.
+###
+### Octave is free software; you can redistribute it and/or modify it
+### under the terms of the GNU General Public License as published by
+### the Free Software Foundation; either version 2, or (at your option)
+### any later version.
+###
+### Octave is distributed in the hope that it will be useful, but
+### WITHOUT ANY WARRANTY; without even the implied warranty of
+### MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+### General Public License for more details.
+###
+### You should have received a copy of the GNU General Public License
+### along with Octave; see the file COPYING.  If not, write to the Free
+### Software Foundation, 59 Temple Place - Suite 330, Boston, MA
+### 02111-1307, USA.
 
 function y = fftfilt (b, x, N)
 
-# usage:  fftfilt (b, x [, N])
-#
-# y = fftfilt (b, x) filters x with the FIR filter b using the FFT.
-# y = fftfilt (b, x, N) uses the overlap-add method to filter x with
-# b using an N-point FFT.
+  ## usage:  fftfilt (b, x [, N])
+  ##
+  ## y = fftfilt (b, x) filters x with the FIR filter b using the FFT.
+  ## y = fftfilt (b, x, N) uses the overlap-add method to filter x with
+  ## b using an N-point FFT.
 
-# Written by KH (Kurt.Hornik@ci.tuwien.ac.at) on Sep 3, 1994
+  ## Written by KH (Kurt.Hornik@ci.tuwien.ac.at) on Sep 3, 1994
 
-# Reference:  Oppenheim & Schafer (1989).  Discrete-time Signal
-# Processing (Chapter 8).  Prentice-Hall.
+  ## Reference:  Oppenheim & Schafer (1989).  Discrete-time Signal
+  ## Processing (Chapter 8).  Prentice-Hall.
 
-# If N is not specified explicitly, we do not use the overlap-add 
-# method at all because loops are really slow.  Otherwise, we only
-# ensure that the number of points in the FFT is the smallest power
-# of two larger than N and length(b).  This could result in length
-# one blocks, but if the user knows better ...
+  ## If N is not specified explicitly, we do not use the overlap-add 
+  ## method at all because loops are really slow.  Otherwise, we only
+  ## ensure that the number of points in the FFT is the smallest power
+  ## of two larger than N and length(b).  This could result in length
+  ## one blocks, but if the user knows better ...
   
   if (nargin < 2 || nargin > 3)
     usage (" fftfilt (b, x [, N])");
@@ -56,12 +57,12 @@
   b = reshape (b, 1, l_b);
   
   if (nargin == 2)
-# Use FFT with the smallest power of 2 which is >= length (x) +
-# length (b) - 1 as number of points ...
+    ## Use FFT with the smallest power of 2 which is >= length (x) +
+    ## length (b) - 1 as number of points ...
     N    = 2^(ceil (log (l_x + l_b - 1) / log(2)));
     y    = ifft (fft (x, N) .* fft(b, N));
   else
-# Use overlap-add method ...
+    ## Use overlap-add method ...
     if !(is_scalar (N))
       error ("fftfilt: N has to be a scalar");
     endif
@@ -81,8 +82,8 @@
     
   y = reshape (y(1:l_x), r_x, c_x);
 
-# Final cleanups:  if both x and b are real respectively integer, y
-# should also be
+  ## Final cleanups:  if both x and b are real respectively integer, y
+  ## should also be
 
   if (! (any (imag (x)) || any (imag (b))))
     y = real (y);