OWSOM: Add warning about ignoring instances with undefined values

Author: janezd

Orange/widgets/unsupervised/owsom.py

@@ -187,6 +187,8 @@ class Warning(OWWidget.Warning):
         ignoring_disc_variables = Msg("SOM ignores discrete variables.")
         missing_colors = \
             Msg("Some data instances have undefined value of '{}'.")
+        missing_values = \
+            Msg("{} data instance{} with undefined value(s) {} not shown.")
 
     class Error(OWWidget.Error):
         no_numeric_variables = Msg("Data contains no numeric columns.")
@@ -311,6 +313,12 @@ def set_data(self, data):
             self.controls.attr_color.model().set_domain(data.domain)
             self.attr_color = data.domain.class_var
 
+            missing = len(data) - len(self.data)
+            if missing == 1:
+                self.Warning.missing_values(1, "", "is")
+            elif missing > 1:
+                self.Warning.missing_values(missing, "s", "are")
+
         self.openContext(self.data)
         self.set_color_bins()
         self.create_legend()

Orange/widgets/unsupervised/tests/test_owsom.py

@@ -89,10 +89,25 @@ def test_missing_some_data(self):
 
         self.send_signal(widget.Inputs.data, self.iris)
         self.assertFalse(widget.Error.no_defined_rows.is_shown())
+        self.assertTrue(widget.Warning.missing_values.is_shown())
         np.testing.assert_almost_equal(
             widget.data.Y.flatten(), [1] * 50 + [2] * 50)
         self.assertEqual(widget.cont_x.shape, (100, 4))
 
+        self.send_signal(widget.Inputs.data, None)
+        self.assertFalse(widget.Warning.missing_values.is_shown())
+
+    def test_missing_one_row_data(self):
+        widget = self.widget
+        self.iris.X[5, 0] = np.nan
+
+        self.send_signal(widget.Inputs.data, self.iris)
+        self.assertFalse(widget.Error.no_defined_rows.is_shown())
+        self.assertTrue(widget.Warning.missing_values.is_shown())
+
+        self.send_signal(widget.Inputs.data, None)
+        self.assertFalse(widget.Warning.missing_values.is_shown())
+
     def test_sparse_data(self):
         widget = self.widget
         self.iris.X = sp.csc_matrix(self.iris.X)