Index: /issm/trunk-jpl/src/m/model/modelextract.m
===================================================================
--- /issm/trunk-jpl/src/m/model/modelextract.m	(revision 11141)
+++ /issm/trunk-jpl/src/m/model/modelextract.m	(revision 11142)
@@ -33,6 +33,9 @@
 end
 
-%first
+%get elements that are inside area
 flag_elem=FlagElements(md1,area);
+if ~any(flag_elem),
+	error('extracted model is empty');
+end
 
 %kick out all elements with 3 dirichlets