Fix: Neighbours: Error when data and reference have different domain.

Author: PrimozGodec

Orange/widgets/data/owneighbors.py

@@ -43,6 +43,9 @@ class Warning(OWWidget.Warning):
         all_data_as_reference = \
             Msg("Every data instance is same as some reference")
 
+    class Error(OWWidget.Error):
+        diff_domains = Msg("Data and reference have different domains.")
+
     n_neighbors = Setting(10)
     distance_index = Setting(0)
     exclude_reference = Setting(True)
@@ -107,10 +110,16 @@ def recompute(self):
         self.apply()
 
     def compute_distances(self):
+        self.Error.diff_domains.clear()
         if self.data is None or len(self.data) == 0 \
                 or self.reference is None or len(self.reference) == 0:
             self.distances = None
             return
+        if self.reference.domain != self.data.domain:
+            self.Error.diff_domains()
+            self.distances = None
+            return
+
         distance = METRICS[self.distance_index][1]
         n_ref = len(self.reference)
         all_data = Table.concatenate([self.reference, self.data], 0)

Orange/widgets/data/tests/test_owneighbors.py

@@ -4,7 +4,7 @@
 
 import numpy as np
 
-from Orange.data import Table, Domain
+from Orange.data import Table, Domain, ContinuousVariable
 from Orange.widgets.data.owneighbors import OWNeighbors, METRICS
 from Orange.widgets.tests.base import WidgetTest, ParameterMapping
 
@@ -343,6 +343,37 @@ def test_all_equal_ref(self):
         self.assertFalse(widget.Warning.all_data_as_reference.is_shown())
         self.assertIsNotNone(self.get_output(widget.Outputs.data))
 
+    def test_different_domains(self):
+        """
+        Test weather widget show error when data and a reference have different
+        domains.
+        """
+        w = self.widget
+
+        domain = Domain([ContinuousVariable("a")])
+        domain_ref = Domain([ContinuousVariable("b")])
+        data = Table(domain, np.random.rand(2, len(domain)))
+        reference = Table(
+            domain_ref, np.random.rand(1, len(domain_ref)))
+
+        # same domain - no error
+        self.send_signal(w.Inputs.data, data)
+        self.send_signal(w.Inputs.reference, data[:1])
+        self.assertFalse(w.Error.diff_domains.is_shown())
+
+        # one attribute different attribute name
+        self.send_signal(w.Inputs.data, data)
+        self.send_signal(w.Inputs.reference, reference)
+        self.assertTrue(w.Error.diff_domains.is_shown())
+
+        # different number of attributes
+        domain_ref = Domain([ContinuousVariable("a"), ContinuousVariable("b")])
+        reference = Table(domain_ref, np.random.rand(1, len(domain_ref)))
+
+        self.send_signal(w.Inputs.data, data)
+        self.send_signal(w.Inputs.reference, reference)
+        self.assertTrue(w.Error.diff_domains.is_shown())
+
 
 if __name__ == "__main__":
     unittest.main()