--- a/scripts/set/setxor.m	Fri Jan 16 08:07:05 2009 +0100
+++ b/scripts/set/setxor.m	Fri Jan 16 08:10:28 2009 +0100
@@ -1,4 +1,5 @@
 ## Copyright (C) 2000, 2006, 2007 Paul Kienzle
+## Copyright (C) 2008 Jaroslav Hajek
 ##
 ## This file is part of Octave.
 ##
@@ -18,22 +19,38 @@
 
 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} setxor (@var{a}, @var{b})
+## @deftypefnx {Function File} {} setxor (@var{a}, @var{b}, 'rows')
 ##
 ## Return the elements exclusive to @var{a} or @var{b}, sorted in ascending
 ## order. If @var{a} and @var{b} are both column vectors return a column
 ## vector, otherwise return a row vector.
 ##
+## @deftypefnx {Function File} {[@var{c}, @var{ia}, @var{ib}] =} setxor (@var{a}, @var{b})
+##
+## Return index vectors @var{ia} and @var{ib} such that @code{a==c(ia)} and
+## @code{b==c(ib)}.
+## 
 ## @seealso{unique, union, intersect, setdiff, ismember}
 ## @end deftypefn
 
-function c = setxor (a, b)
-  if (nargin != 2)
+function [c, ia, ib] = setxor (a, b, varargin)
+
+  if (nargin < 2 || nargin > 3)
     print_usage ();
   endif
 
+  if (nargin == 3 && ! strcmpi (varargin{1}, "rows"))
+    error ("setxor: if a third input argument is present, it must be the string 'rows'");
+  endif
+
   ## Form A and B into sets.
-  a = unique (a);
-  b = unique (b);
+  if (nargout > 1)
+    [a, ia] = unique (a, varargin{:});
+    [b, ib] = unique (b, varargin{:});
+  else
+    a = unique (a, varargin{:});
+    b = unique (b, varargin{:});
+  endif
 
   if (isempty (a))
     c = b;
@@ -41,16 +58,39 @@
     c = a;
   else
     ## Reject duplicates.
-    c = sort ([a(:); b(:)]);
-    n = length (c);
-    idx = find (c(1:n-1) == c(2:n));
-    if (! isempty (idx))
-      c([idx, idx+1]) = [];
-    endif
-    if (size (a, 1) == 1 || size (b, 1) == 1)
-      c = c.';
+    if (nargin > 2)
+      na = rows (a); nb = rows (b);
+      [c, i] = sortrows ([a; b]);
+      n = rows (c);
+      idx = find (all (c(1:n-1) == c(2:n), 2));
+      if (! isempty (idx))
+	c([idx, idx+1],:) = [];
+	i([idx, idx+1],:) = [];
+      endif
+    else
+      na = numel (a); nb = numel (b);
+      [c, i] = sort ([a(:); b(:)]);
+      n = length (c);
+      idx = find (c(1:n-1) == c(2:n));
+      if (! isempty (idx))
+	c([idx, idx+1]) = [];
+	i([idx, idx+1]) = [];
+      endif
+      if (size (a, 1) == 1 || size (b, 1) == 1)
+	c = c.';
+      endif
     endif
   endif
+  if (nargout > 1)
+    ia = ia(i(i <= na));
+    ib = ib(i(i > na) - na);
+  endif
+
 endfunction
 
 %!assert(setxor([1,2,3],[2,3,4]),[1,4])
+%!test
+%! a = [3, 1, 4, 1, 5]; b = [1, 2, 3, 4];
+%! [y, ia, ib] = setxor (a, b.');
+%! assert(y, [2, 5]);
+%! assert(y, sort([a(ia), b(ib)]));