[processing] fix handling of NULLs is Basic statistics for text fields

alexbruy · alexbruy · commit d3852e481e43 · 2016-02-22T13:35:13.000+02:00
diff --git a/python/plugins/processing/algs/qgis/BasicStatisticsStrings.py b/python/plugins/processing/algs/qgis/BasicStatisticsStrings.py
@@ -84,8 +84,8 @@ def processAlgorithm(self, progress):
         minValue = 0
         maxValue = 0
         meanValue = 0
-        countEmpty = 0
-        countFilled = 0
+        nullValues = 0
+        filledValues = 0
 
         isFirst = True
         values = []
@@ -94,7 +94,14 @@ def processAlgorithm(self, progress):
         count = len(features)
         total = 100.0 / count
         for current, ft in enumerate(features):
-            length = float(len(ft.attributes()[index]))
+            value = ft[fieldName]
+            if value:
+                length = float(len(value))
+                filledValues += 1
+            else:
+                nullValues += 1
+                progress.setPercentage(int(current * total))
+                continue
 
             if isFirst:
                 minValue = length
@@ -106,11 +113,6 @@ def processAlgorithm(self, progress):
                 if length > maxValue:
                     maxValue = length
 
-            if length != 0.00:
-                countFilled += 1
-            else:
-                countEmpty += 1
-
             values.append(length)
             sumValue += length
 
@@ -128,8 +130,8 @@ def processAlgorithm(self, progress):
         data.append('Minimum length: ' + unicode(minValue))
         data.append('Maximum length: ' + unicode(maxValue))
         data.append('Mean length: ' + unicode(meanValue))
-        data.append('Filled: ' + unicode(countFilled))
-        data.append('Empty: ' + unicode(countEmpty))
+        data.append('Filled values: ' + unicode(filledValues))
+        data.append('NULL (missed) values: ' + unicode(nullValues))
         data.append('Count: ' + unicode(count))
         data.append('Unique: ' + unicode(uniqueValues))
 
@@ -138,8 +140,8 @@ def processAlgorithm(self, progress):
         self.setOutputValue(self.MIN_LEN, minValue)
         self.setOutputValue(self.MAX_LEN, maxValue)
         self.setOutputValue(self.MEAN_LEN, meanValue)
-        self.setOutputValue(self.FILLED, countFilled)
-        self.setOutputValue(self.EMPTY, countEmpty)
+        self.setOutputValue(self.FILLED, filledValues)
+        self.setOutputValue(self.EMPTY, nullValues)
         self.setOutputValue(self.COUNT, count)
         self.setOutputValue(self.UNIQUE, uniqueValues)
 
diff --git a/python/plugins/processing/tests/testdata/algorithm_tests.yaml b/python/plugins/processing/tests/testdata/algorithm_tests.yaml
@@ -63,6 +63,7 @@ tests:
       OUTPUT:
         name: expected/polys_to_lines.gml
         type: vector
+
   - algorithm: qgis:basicstatisticsfornumericfields
     name: Test (qgis:basicstatisticsfornumericfields)
     params:
@@ -73,3 +74,14 @@ tests:
       OUTPUT_HTML_FILE:
         name: expected/basic_statistics_numeric_float.html
         type: file
+
+  - algorithm: qgis:basicstatisticsfortextfields
+    name: Test (qgis:basicstatisticsfortextfields)
+    params:
+    - name: multipolys.gml
+      type: vector
+    - 'Bname'
+    results:
+      OUTPUT_HTML_FILE:
+        name: expected/basic_statistics_string.html
+        type: file
diff --git a/python/plugins/processing/tests/testdata/expected/basic_statistics_string.html b/python/plugins/processing/tests/testdata/expected/basic_statistics_string.html
@@ -0,0 +1,12 @@
+<html><head>
+<meta http-equiv="Content-Type" content="text/html;                 charset=utf-8" /></head><body>
+<p>Analyzed layer: multipolys.gml</p>
+<p>Analyzed field: Bname</p>
+<p>Minimum length: 4.0</p>
+<p>Maximum length: 4.0</p>
+<p>Mean length: 4.0</p>
+<p>Filled values: 3</p>
+<p>NULL (missed) values: 1</p>
+<p>Count: 4</p>
+<p>Unique: 2</p>
+</body></html>
