Update head hyperparam to use highest weight

bayesclass/tests/test_bayesclass.py

@@ -16,12 +16,26 @@ def data():
     return enc.fit_transform(X), y
 
 
-def test_TAN_classifier(data):
+def test_TAN_constructor():
     clf = TAN()
-
     # Test default values of hyperparameters
     assert not clf.simple_init
     assert not clf.show_progress
+    assert clf.random_state is None
+    clf = TAN(simple_init=True, show_progress=True, random_state=17)
+    assert clf.simple_init
+    assert clf.show_progress
+    assert clf.random_state == 17
+
+
+def test_TAN_random_head(data):
+    clf = TAN(random_state=17)
+    clf.fit(*data, head="random")
+    assert clf.head_ == 3
+
+
+def test_TAN_classifier(data):
+    clf = TAN()
 
     clf.fit(*data)
     attribs = ["classes_", "X_", "y_", "head_", "features_", "class_name_"]