provide column for standard deviation on single question report - but keep inactive at the moment

knowledge/survey/browser.py

@@ -23,6 +23,7 @@ surveys and self-assessments.
 
 import csv
 from cStringIO import StringIO
+import math
 from zope.app.pagetemplate import ViewPageTemplateFile
 from zope.cachedescriptors.property import Lazy
 from zope.i18n import translate
@@ -269,8 +270,12 @@ class SurveyView(InstitutionMixin, ConceptView):
             average = float(sum(values)) / len(values)
             if question.revertAnswerOptions:
                 average = question.answerRange - average - 1
+            devs = [(average - v) for v in values]
+            stddev = math.sqrt(sum(d * d for d in devs) / len(values))
             average = average * 100 / (question.answerRange - 1)
+            stddev = stddev * 100 / (question.answerRange - 1)
             result['average'] = int(round(average))
+            result['stddev'] = int(round(stddev))
         texts = [r.texts.get(question) for r in self.teamData]
         result['texts'] = '<br />'.join([unicode(t) for t in texts if t])
         return result

knowledge/survey/view_macros.pt

@@ -178,10 +178,12 @@
           <tr>
             <td>&nbsp;</td>
             <td>&nbsp;</td>
+            <!--<td>&nbsp;</td>-->
           </tr>
           <tr class="vpad">
             <td><b tal:content="group/title" /></td>
             <td i18n:translate="">Average</td>
+            <!--<td i18n:translate="">Deviation</td>-->
           </tr>
           <tr tal:repeat="question group/questions">
             <tal:question 
@@ -197,6 +199,9 @@
               <td class="center">
                 <span tal:condition="python:qutype == 'value_selection'"
                       tal:content="data/average" /></td>
+              <!--<td class="center">
+                <span tal:condition="python:qutype == 'value_selection'"
+                      tal:content="data/stddev" /></td>-->
             </tal:question>
           </tr>
         </tal:group>

locales/de/LC_MESSAGES/loops.po

@@ -342,6 +342,9 @@ msgstr "Rang Team"
 msgid "Average"
 msgstr "Durchschnitt"
 
+msgid "Deviation"
+msgstr "Abweichung"
+
 msgid "Team Size"
 msgstr "Anzahl der vom Team ausgefüllten Fragebögen"