+//backwards compat\r
+Ext.grid.GroupSummary = Ext.ux.grid.GroupSummary;\r
+\r
+\r
+/**\r
+ * Calculation types for summary row:</p><div class="mdetail-params"><ul>\r
+ * <li><b><tt>sum</tt></b> : <div class="sub-desc"></div></li>\r
+ * <li><b><tt>count</tt></b> : <div class="sub-desc"></div></li>\r
+ * <li><b><tt>max</tt></b> : <div class="sub-desc"></div></li>\r
+ * <li><b><tt>min</tt></b> : <div class="sub-desc"></div></li>\r
+ * <li><b><tt>average</tt></b> : <div class="sub-desc"></div></li>\r
+ * </ul></div>\r
+ * <p>Custom calculations may be implemented. An example of\r
+ * custom <code>summaryType=totalCost</code>:</p><pre><code>\r
+// define a custom summary function\r
+Ext.ux.grid.GroupSummary.Calculations['totalCost'] = function(v, record, field){\r
+ return v + (record.data.estimate * record.data.rate);\r
+};\r
+ * </code></pre>\r
+ * @property Calculations\r
+ */\r
+\r
+Ext.ux.grid.GroupSummary.Calculations = {\r