Request for indexing fix

[David Bateman]

Matlab allows the following code

x = randn(2,2,2);
idx(1:3) = {1};
idx(1) =';';
x(idx{:})

This is a really nice feature and I used it in the spline code I
committed. However, it seems that Octave doesn't allow this, and so the
ND spline code is in fact partially broken. I therefore suggest the
attached patch. One point however is that this means that x(':',1,1)
will give the same result, and without access to matlab at the moment
I'm unsure what matlab in fact does in this case.

D.

Index: src/ov-ch-mat.cc
===================================================================
RCS file: /usr/local/cvsroot/octave/src/ov-ch-mat.cc,v
retrieving revision 1.27
diff -u -r1.27 ov-ch-mat.cc
--- src/ov-ch-mat.cc    3 Jun 2007 20:58:29 -0000       1.27
+++ src/ov-ch-mat.cc    13 Jun 2007 23:01:17 -0000
@@ -44,6 +44,16 @@
 DEFINE_OV_TYPEID_FUNCTIONS_AND_DATA (octave_char_matrix,
                                     "char matrix", "int8");
 
+idx_vector 
+octave_char_matrix::index_vector (void) const
+{ 
+  const char *p = matrix.data ();
+  if (numel () == 1 && *p == ':')
+    return idx_vector (':');
+  else
+    return idx_vector (array_value (true)); 
+}
+
 bool
 octave_char_matrix::valid_as_scalar_index (void) const
 {
Index: src/ov-ch-mat.h
===================================================================
RCS file: /usr/local/cvsroot/octave/src/ov-ch-mat.h,v
retrieving revision 1.44
diff -u -r1.44 ov-ch-mat.h
--- src/ov-ch-mat.h     22 Jul 2006 08:31:17 -0000      1.44
+++ src/ov-ch-mat.h     13 Jun 2007 23:01:17 -0000
@@ -80,8 +80,7 @@
   octave_base_value *clone (void) const { return new octave_char_matrix 
(*this); }
   octave_base_value *empty_clone (void) const { return new octave_char_matrix 
(); }
 
-  idx_vector index_vector (void) const
-    { return idx_vector (array_value (true)); }
+  idx_vector index_vector (void) const;
 
   bool is_char_matrix (void) const { return true; }
   bool is_real_matrix (void) const { return true; }