# HG changeset patch
# User Soren Hauberg <hauberg@gmail.com>
# Date 1267828187 28800
# Node ID b14fd5116c298f626c2349035b8e9bd3dc6209eb
# Parent  81bcdf5fd7a903c06d834bbd670a143eec5dbe5f
Ensure that 'limits' is a 2 or 4 vector, and that 'fn' is a function

diff --git a/scripts/ChangeLog b/scripts/ChangeLog
--- a/scripts/ChangeLog
+++ b/scripts/ChangeLog
@@ -1,3 +1,8 @@
+2010-03-05  Soren Hauberg  <hauberg@gmail.com>
+
+	* plot/fplot.m: Ensure that 'limits' is a 2 or 4 vector, and that 'fn' is a
+	function.
+
 2010-03-05  Jaroslav Hajek  <highegg@gmail.com>
 
 	* testfun/test.m: Support catching warnings and errors by IDs.
diff --git a/scripts/plot/fplot.m b/scripts/plot/fplot.m
--- a/scripts/plot/fplot.m
+++ b/scripts/plot/fplot.m
@@ -46,6 +46,10 @@
     print_usage ();
   endif
 
+  if (!isreal (limits) || (numel (limits) != 2 && numel (limits) != 4))
+    error ("fplot: second input argument must be a real vector with 2 or 4 elements");
+  endif
+
   if (nargin < 3) 
     n = 0.002; 
   endif
@@ -68,9 +72,11 @@
     nam = func2str (fn);
   elseif (all (isalnum (fn)))
     nam = fn;
+  elseif (ischar (fn))
+     fn = vectorize (inline (fn));
+     nam = formula (fn);
   else
-    fn = vectorize (inline (fn));
-    nam = formula (fn);
+    error ("fplot: first input argument must be a function handle, inline function or string");
   endif
 
   if (floor(n) != n)