# HG changeset patch
# User Sebastien Loisel
# Date 1204711134 18000
# Node ID b1368dc9e719f9e9748fc5ccc09dbb66b75f749f
# Parent  a6e08ecb405003da4e4fcf2ab1a205e029437f8e
Apply a scaling factor to leading zero removal in roots.m

diff -r a6e08ecb4050 -r b1368dc9e719 scripts/ChangeLog
--- a/scripts/ChangeLog	Mon Mar 03 20:00:17 2008 -0500
+++ b/scripts/ChangeLog	Wed Mar 05 04:58:54 2008 -0500
@@ -1,3 +1,12 @@
+2008-03-05  Ben Abbott  <bpabbott@mac.com>
+
+	* polynomial/roots.m: Catch Infs and/or NaNs.
+
+2008-03-05  Sebastien Loisel  <loisel@temple.edu>
+
+	* polynomial/roots.m: Apply a scaling factor to the removal of the
+	leading zeros.
+
 2008-02-29  John W. Eaton  <jwe@octave.org>
 
 	* plot/print.m: Handle gif and jpg devices.
diff -r a6e08ecb4050 -r b1368dc9e719 scripts/polynomial/roots.m
--- a/scripts/polynomial/roots.m	Mon Mar 03 20:00:17 2008 -0500
+++ b/scripts/polynomial/roots.m	Wed Mar 05 04:58:54 2008 -0500
@@ -83,16 +83,22 @@
 
   if (nargin != 1 || min (size (v)) > 1)
     print_usage ();
+  elseif (any (isnan(v) | isinf(v)))
+    error ("roots: inputs must not contain Inf or NaN")
   endif
 
-  n = length (v);
-  v = reshape (v, 1, n);
+  n = numel (v);
+  v = v(:);
 
   ## If v = [ 0 ... 0 v(k+1) ... v(k+l) 0 ... 0 ], we can remove the
   ## leading k zeros and n - k - l roots of the polynomial are zero.
 
-  f = find (v);
-  m = max (size (f));
+  if (isempty (v))
+    f = v;
+  else
+    f = find (v ./ max (abs (v)));
+  endif
+  m = numel (f);
 
   if (m > 0 && n > 1)
     v = v(f(1):f(m));