Another map reduce example.

bt5/erp5_wendelin_examples/ExtensionTemplateItem/portal_components/extension.erp5.WendelinExamples.py

@@ -212,5 +212,12 @@ def game_of_life(self):
   for i in range(4): 
     iterate_2(Z)
     print_list.append(str(Z))
+
+  return '\n\n'.join(print_list)
   
-  return '\n\n'.join(print_list)
\ No newline at end of file
+def DataArray_calculateArraySliceAverageAndStore(self, start, end):
+  """
+    Compute average on a data array slice and store result on an Active Process.
+  """
+  zarray = self.getArray()
+  return np.average(zarray[start:end])
\ No newline at end of file

bt5/erp5_wendelin_examples/SkinTemplateItem/portal_skins/erp5_wendelin_examples/DataArray_calculateArraySliceAverageAndStore.xml

+<?xml version="1.0"?>
+<ZopeData>
+  <record id="1" aka="AAAAAAAAAAE=">
+    <pickle>
+      <global name="ExternalMethod" module="Products.ExternalMethod.ExternalMethod"/>
+    </pickle>
+    <pickle>
+      <dictionary>
+        <item>
+            <key> <string>_function</string> </key>
+            <value> <string>DataArray_calculateArraySliceAverageAndStore</string> </value>
+        </item>
+        <item>
+            <key> <string>_module</string> </key>
+            <value> <string>WendelinExamples</string> </value>
+        </item>
+        <item>
+            <key> <string>id</string> </key>
+            <value> <string>DataArray_calculateArraySliceAverageAndStore</string> </value>
+        </item>
+        <item>
+            <key> <string>title</string> </key>
+            <value> <string></string> </value>
+        </item>
+      </dictionary>
+    </pickle>
+  </record>
+</ZopeData>