# HG changeset patch
# User Ben Abbott <address@hidden>
# Date 1204684452 18000
# Node ID 4f4f020bcf7cd28b56b32cfb0eae83dbb9c314f6
# Parent  6070c3bd69c44a75b8c5a0f72056df36cf348564
roots.m: Catch Infs and NaNs.

diff -r 6070c3bd69c4 -r 4f4f020bcf7c scripts/ChangeLog
--- a/scripts/ChangeLog	Tue Mar 04 17:01:05 2008 -0500
+++ b/scripts/ChangeLog	Tue Mar 04 21:34:12 2008 -0500
@@ -1,3 +1,7 @@ 2008-03-04  Bill Denney  <address@hidden
+2008-03-04  Bill Denney  <address@hidden>
+
+	* polynomial/roots.m: Modified to catch Infs and/or NaNs.
+ 
 2008-03-04  Bill Denney  <address@hidden>
 
 	* geometry/rectint.m: New function.
diff -r 6070c3bd69c4 -r 4f4f020bcf7c scripts/polynomial/roots.m
--- a/scripts/polynomial/roots.m	Tue Mar 04 17:01:05 2008 -0500
+++ b/scripts/polynomial/roots.m	Tue Mar 04 21:34:12 2008 -0500
@@ -83,16 +83,18 @@ function r = roots (v)
 
   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));
+  m = numel (f);
 
   if (m > 0 && n > 1)
     v = v(f(1):f(m));
@@ -114,9 +116,20 @@ function r = roots (v)
 
 endfunction
 
+%!test
+%! p = [poly([3 3 3 3]), 0 0 0 0];
+%! r = sort (roots (p));
+%! assert (r, [0; 0; 0; 0; 3; 3; 3; 3], 0.001)
+
 %!assert(all (all (abs (roots ([1, -6, 11, -6]) - [3; 2; 1]) < sqrt (eps))));
 
 %!assert(isempty (roots ([])));
 
+%!assert(isempty (roots (1)));
+
 %!error roots ([1, 2; 3, 4]);
 
+%!error roots ([1 Inf 1]);
+
+%!error roots ([1 NaN 1]);
+