ishold.m: Code cleanup of variable names.

* ishold.m: Rename variable "fig" to "hfig" and "ax" to "hax" to emphasize that
they hold graphics handles.  Use numel() in preference to length().  Add one
more case to existing BIST test.

Author: Rik

scripts/plot/util/ishold.m

@@ -38,30 +38,30 @@
 function tf = ishold (h)
 
   if (nargin == 0)
-    fig = gcf ();
-    ax = get (fig, "currentaxes");
+    hfig = gcf ();
+    hax = get (hfig, "currentaxes");
   else
     if (! ishghandle (h))
       error ("ishold: H must be an axes or figure graphics handle");
     endif
 
     switch (get (h, "type"))
       case "figure"
-        fig = h;
-        ax = get (fig, "currentaxes");
+        hfig = h;
+        hax = get (hfig, "currentaxes");
 
       case "axes"
-        ax = h;
-        fig = ancestor (ax, "figure");
+        hax = h;
+        hfig = ancestor (hax, "figure");
 
       otherwise
         error ("ishold: H must be an axes or figure graphics handle");
 
     endswitch
   endif
 
-  tf = (strcmp (get (fig, "nextplot"), "add")
-            && ! isempty (ax) && strcmp (get (ax, "nextplot"), "add"));
+  tf = (strcmp (get (hfig, "nextplot"), "add")
+        && ! isempty (hax) && strcmp (get (hax, "nextplot"), "add"));
 
 endfunction
 
@@ -83,8 +83,11 @@
 %!   assert (get (gca, "NextPlot"), "add");
 %!   assert (get (hf, "NextPlot"), "add");
 %!   p = fill ([0 1 1], [0 0 1],"black");
-%!   assert (length (get (hf, "children")), 1);
-%!   assert (length (get (gca, "children")), 2);
+%!   assert (numel (get (hf, "children")), 1);
+%!   assert (numel (get (gca, "children")), 2);
+%!   set (hf, "NextPlot", "new");
+%!   assert (! ishold);
+%!   assert (! ishold (gca));
 %! unwind_protect_cleanup
 %!   close (hf);
 %! end_unwind_protect