--- a/scripts/signal/autoreg_matrix.m
+++ b/scripts/signal/autoreg_matrix.m
@@ -1,15 +1,15 @@
 ## Copyright (C) 1995, 1996, 1997  Kurt Hornik
-## 
+##
 ## This program 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.
-## 
+##
 ## This program 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. 
-## 
+## General Public License for more details.
+##
 ## You should have received a copy of the GNU General Public License
 ## along with this file.  If not, write to the Free Software Foundation,
 ## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
@@ -20,7 +20,7 @@
 ## first column and the first k lagged values of y in the other columns.
 ## I.e., for t > k, [1, y(t-1), ..., y(t-k)] is the t-th row of X. X can
 ## be used as regressor matrix in autoregressions.
-  
+
 ## Author:  KH <Kurt.Hornik@ci.tuwien.ac.at>
 ## Description:  Design matrix for autoregressions
 
@@ -29,16 +29,16 @@
   if (nargin != 2)
     usage ("autoreg_matrix (y, k)");
   endif
-  
+
   if !(is_vector (y))
     error ("autoreg_matrix:  y must be a vector");
   endif
-  
+
   T = length (y);
   y = reshape (y, T, 1);
   X = ones (T, k+1);
   for j = 1 : k;
     X(:, j+1) = [(zeros (j, 1)); y(1:T-j)];
   endfor
-  
+
 endfunction