dont assume plotter params exist

beat/web/search/templatetags/search_tags.py

@@ -210,7 +210,7 @@ def plot_details_for_result(r):
 
     return dict(
             plotter=plotting['default'][0].fullname(),
-            parameter=plotting['default'][1].fullname(),
+            parameter=None if plotting['default'][1] == None else plotting['default'][1].fullname(),
             parameters=json.dumps([k.fullname() for k in plotting['options'][plotting['default'][0]]]),
             )