FIX Model: interaction with Var

eelbrain/_data_obj.py

@@ -18,6 +18,20 @@
 
     * Dataset
 
+
+Effect types
+------------
+
+These are elementary effects in a Model, and identified by :func:`is_effect`
+
+ - _Effect
+   - Factor
+   - Interaction
+   - NestedEffect
+ - Var
+ - NonBasicEffect
+
+
 """
 
 from __future__ import division
@@ -1608,7 +1622,9 @@ def __rsub__(self, other):
         return Var(x, info=info)
 
     def __mul__(self, other):
-        if iscategorial(other):
+        if isinstance(other, Model):
+            return Model((self,)) * other
+        elif iscategorial(other):
             return Model((self, other, self % other))
         elif isinstance(other, Var):
             x = self.x * other.x
@@ -6087,7 +6103,7 @@ class Interaction(_Effect):
 
     Parameters
     ----------
-    base : list
+    base : sequence
         List of data-objects that form the basis of the interaction.
 
     Attributes
@@ -6581,7 +6597,10 @@ def __mod__(self, other):
         out = []
         for e_self in self.effects:
             for e_other in Model(other).effects:
-                out.append(e_self % e_other)
+                if isinstance(e_self, Var) and isinstance(e_other, Var):
+                    out.append(e_self * e_other)
+                else:
+                    out.append(e_self % e_other)
         return Model(out)
 
     def __eq__(self, other):

eelbrain/tests/test_data.py

@@ -706,6 +706,7 @@ def test_model():
     "Test Model class"
     a = Factor('ab', repeat=3, name='a')
     b = Factor('ab', tile=3, name='b')
+    u = Var([1, 1, 1, -1, -1, -1], 'u')
     v = Var([1., 2., 3., 4., 5., 6.], 'v')
     w = Var([1., 0., 0., 1., 1., 0.], 'w')
 
@@ -752,6 +753,22 @@ def test_model():
     mp = pickle.loads(pickle.dumps(m, pickle.HIGHEST_PROTOCOL))
     assert_array_equal(m.full, mp.full)
 
+    # nested Vars
+    m = (v + w) * u
+    assert_dataobj_equal(m.effects[2], u)
+    assert_dataobj_equal(m.effects[3], v * u)
+    assert_dataobj_equal(m.effects[4], w * u)
+    m = u * (v + w)
+    assert_dataobj_equal(m.effects[0], u)
+    assert_dataobj_equal(m.effects[3], u * v)
+    assert_dataobj_equal(m.effects[4], u * w)
+    m = (v + w) % u
+    assert_dataobj_equal(m.effects[0], v * u)
+    assert_dataobj_equal(m.effects[1], w * u)
+    m = u % (v + w)
+    assert_dataobj_equal(m.effects[0], u * v)
+    assert_dataobj_equal(m.effects[1], u * w)
+
 
 def test_ndvar():
     "Test the NDVar class"