--- a/liboctave/Array2-idx.h
+++ b/liboctave/Array2-idx.h
@@ -160,32 +160,10 @@
 
   if (idx_i && idx_j)
     {
-      if (idx_i.orig_empty () || idx_j.orig_empty ())
+      if (idx_i.orig_empty () || idx_j.orig_empty () || n == 0 || m == 0)
 	{
 	  retval.resize (n, m);
 	}
-      else if (n == 0)
-	{
-	  if (m == 0)
-	    retval.resize (0, 0);
-	  else if (idx_j.is_colon_equiv (nc, 1))
-	    retval.resize (0, nc);
-	  else if (idx_i.is_colon_equiv (nr, 1))
-	    retval.resize (0, m);
-	  else
-	    (*current_liboctave_error_handler) ("invalid row index = 0");
-	}
-      else if (m == 0)
-	{
-	  if (n == 0)
-	    retval.resize (0, 0);
-	  else if (idx_i.is_colon_equiv (nr, 1))
-	    retval.resize (nr, 0);
-	  else if (idx_j.is_colon_equiv (nc, 1))
-	    retval.resize (n, 0);
-	  else
-	    (*current_liboctave_error_handler) ("invalid column index = 0");
-	}
       else if (idx_i.is_colon_equiv (nr) && idx_j.is_colon_equiv (nc))
 	{
 	  retval = *this;

--- a/liboctave/ChangeLog
+++ b/liboctave/ChangeLog
@@ -1,3 +1,8 @@
+2002-04-23  John W. Eaton  <jwe@bevo.che.wisc.edu>
+
+	* Array2-idx.h (Array2<T>::index (idx_vector&, idx_vector&) const):
+	Simplify indexing when one or both of the indices are empty.
+
 2002-04-11  John W. Eaton  <jwe@bevo.che.wisc.edu>
 
 	* DASSL.h (DASSL_options::init): Set absolute tolerance to eps ^ 2.

--- a/scripts/ChangeLog
+++ b/scripts/ChangeLog
@@ -1,3 +1,8 @@
+2002-04-23  Paul Kienzle <pkienzle@users.sf.net>
+
+	* image/rgb2hsv.m: Faster, more accurate, remove the
+	divide by zero warning.
+
 2002-04-09  Paul Kienzle <pkienzle@users.sf.net>
 
 	* strings/deblank.m: Trim \0 as well as blank.

--- a/scripts/image/rgb2hsv.m
+++ b/scripts/image/rgb2hsv.m
@@ -43,48 +43,40 @@
     error ("rgb2hsv: argument must be a matrix of size n x 3");
   endif
 
-  # get saturation and value
-  v = max (rgb');
-  s = (v' > 0) .* (1 .- min (rgb') ./ v)';
-
-  # if v==0 set s to 0 too
-  s(isnan (s)) = 0;
+  ## get the max and min
+  s = min (rgb')';
+  v = max (rgb')';
 
-  # subtract minimum and divide trough maximum
-  # to get the bright and saturated colors
-  sc = (rgb - kron ([1, 1, 1], min (rgb')'));
-  sv = sc ./ kron([1, 1, 1], max (sc')');
-
-  # if r=g=b (gray value) set hue to 0
-  sv(isnan (sv)) = 0;
-
-  # hue=f(color) must be splitted into 6 parts 
-  # 2 for each color
+  ## set hue to zero for undefined values (gray has no hue)
+  h = zeros (size (v));
+  notgray = (s != v);
+    
+  ## blue hue
+  idx = (v == rgb(:,3) & notgray);
+  if (any (idx))
+    h(idx) = 2/3 + 1/6 * (rgb(idx,1) - rgb(idx,2)) ./ (v(idx) - s(idx));
+  endif
 
-  # h1(green)
-  tmp = (sv(:, 1) == 1 & sv(:,3) == 0) .* (1/6 * sv(:,2) + eps);
-  # avoid problems with h2(red) since hue(0)==hue(1)
-  h = (tmp < 1/6) .* tmp; 
-  # h2(green)
-  h = h + ((h == 0) & sv(:,1) == 0 & sv(:,3) == 1) \
-      .* (-1/6 * sv(:,2) + 2/3 + eps);
-
-  # h1(red)
-  h = h + ((h == 0) & sv(:,2) == 1 & sv(:,3) == 0) \
-      .* (-1/6 * sv(:,1) + 1/3 + eps);
+  ## green hue
+  idx = (v == rgb(:,2) & notgray);
+  if (any (idx))
+    h(idx) = 1/3 + 1/6 * (rgb(idx,3) - rgb(idx,1)) ./ (v(idx) - s(idx));
+  endif
 
-  # h2(red)
-  h = h + ((h == 0) & sv(:,2) == 0 & sv(:,3) == 1) \
-      .* (1/6 * sv(:,1) + 2/3 + eps);
+  ## red hue
+  idx = (v == rgb(:,1) & notgray);
+  if (any (idx))
+    h(idx) =       1/6 * (rgb(idx,2) - rgb(idx,3)) ./ (v(idx) - s(idx));
+  endif
 
-  # h1(blue)
-  h = h + ((h == 0) & sv(:,1) == 1 & sv(:,2) == 0) \
-      .* (-1/6 * sv(:,3) + 1 + eps);
+  ## correct for negative red
+  idx = (h < 0);
+  h(idx) = 1+h(idx);
 
-  # h2(blue)
-  h = h + ((h == 0) & sv(:,1) == 0 & sv(:,2) == 1) \
-      .* (1/6 * sv(:,3) + 1/3);
+  ## set the saturation
+  s(! notgray) = 0;
+  s(notgray) = 1 - s(notgray) ./ v(notgray);
 
-  hsval = [h, s, v'];
+  hsval = [h, s, v];
 
 endfunction