--- a/+sbp/D4Variable.m	Wed Sep 28 16:31:06 2016 +0200
+++ b/+sbp/D4Variable.m	Thu Sep 29 12:56:37 2016 +0200
@@ -16,6 +16,7 @@
         d2_l, d2_r % Left and right boundary second derivative
         d3_l, d3_r % Left and right boundary third derivative
         borrowing % Struct with borrowing limits for different norm matrices
+        order
     end
 
     methods
@@ -46,6 +47,7 @@
             end
 
             obj.m = m;
+            obj.order = order;
 
             obj.H    = H;
             obj.HI   = HI;
@@ -62,5 +64,9 @@
             obj.d3_l = d3_l;
             obj.d3_r = d3_r;
         end
+
+        function str = string(obj)
+            str = [class(obj) '_' num2str(obj.order)];
+        end
     end
 end
\ No newline at end of file