correct check if extra_arg_sf2sig is a string with []

git-svn-id: https://spcsvn.epfl.ch/repos/TCV/gdat/trunk@9126 d63d8f72-b253-0410-a779-e742ad2e26cf

crpptbx/AUG/rdaAUG_eff.m

@@ -93,7 +93,7 @@ else
   % use sf2sig
   if isempty(time_int)
     try
-      if ~isempty(extra_arg_sf2sig)
+      if ~strcmp(extra_arg_sf2sig,'[]')
 	eval(['[adata,adata_time, adata_area]=sf2sig(diagname,shot,sigtype,''-exp'',shotfile_exp,' extra_arg_sf2sig ');']);
       else
 	[adata,adata_time, adata_area]=sf2sig(diagname,shot,sigtype,'-exp',shotfile_exp);