changeset 3210:258d7b26c719

[project @ 1998-11-05 04:00:42 by jwe]
author jwe
date Thu, 05 Nov 1998 04:00:42 +0000
parents fbb332b96e4f
children 440b2b28e74a
files scripts/general/is_duplicate_entry.m scripts/general/is_symmetric.m
diffstat 2 files changed, 51 insertions(+), 11 deletions(-) [+]
line wrap: on
line diff
new file mode 100644
--- /dev/null
+++ b/scripts/general/is_duplicate_entry.m
@@ -0,0 +1,44 @@
+## Copyright (C) 1996, 1997 A. S. Hodel <scotte@eng.auburn.edu>
+##
+## 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.
+
+## Usage: is_duplicate_entry (x)
+##
+## Return non-zero if any entries in x are duplicates of one another.
+
+## Author: A. S. Hodel <scotte@eng.auburn.edu>
+
+function retval = is_duplicate_entry (x)
+
+  if (nargin == 1)
+    if (is_matrix (x))
+      [m, n] = size (x);
+      lx = m*n;
+      lx1 = lx-1;
+      x = sort (reshape (x, 1, lx));
+      dx = x(1:lx1) - x(2:lx);
+      retval = sum (dx == 0);
+    else
+      error ("is_duplicate_entry: expecting matrix argument");
+    endif
+  else
+    usage ("is_duplicate_entry (x)");
+  endif
+
+endfunction
+  
--- a/scripts/general/is_symmetric.m
+++ b/scripts/general/is_symmetric.m
@@ -30,18 +30,14 @@
 
 function retval = is_symmetric (x,tol)
 
-  retval = 0;
-
   if (nargin == 1 || nargin == 2)
-    if (is_matrix (x))
-      [nr, nc] = size (x);
-      if (nr == nc && nr > 0)
-      	if (nargin == 1)
-	  tol = eps;
-      	endif
-      	if (norm (x - x') / norm(x) <= tol)
-          retval = nr;
-      	endif
+    retval = is_square (x);
+    if (retval != 0)
+      if (nargin == 1)
+	tol = eps;
+      endif
+      if (norm (x - x') / norm(x) > tol)
+        retval = 0;
       endif
     endif
   else