Add deterministic test

Author: canyon289

pymc3/tests/test_model.py

@@ -16,6 +16,7 @@
 import theano
 import theano.tensor as tt
 import numpy as np
+import pickle
 import pandas as pd
 import numpy.testing as npt
 import unittest
@@ -423,21 +424,24 @@ def test_tempered_logp_dlogp():
     npt.assert_allclose(func_temp_nograd(x), func_temp(x)[0])
 
 
-import pickle
 def test_model_pickle(tmpdir):
     """Tests that PyMC3 models are pickleable"""
+    with pm.Model() as model:
+        x = pm.Normal('x')
+        pm.Normal('y', observed=1)
+
+    file_path = tmpdir.join("model.p")
+    with open(file_path, 'wb') as buff:
+        pickle.dump(model, buff)
 
-    # Data of the Eight Schools Model
-    J = 8
-    y = np.array([28., 8., -3., 7., -1., 1., 18., 12.])
-    sigma = np.array([15., 10., 16., 11., 9., 11., 10., 18.])
 
+def test_model_pickle_deterministic(tmpdir):
+    """Tests that PyMC3 models are pickleable"""
     with pm.Model() as model:
-        mu = pm.Normal('mu', mu=0, sigma=5)
-        tau = pm.HalfCauchy('tau', beta=5)
-        theta = pm.Normal('theta', mu=mu, sigma=tau, shape=J)
-        obs = pm.Normal('obs', mu=theta, sigma=sigma, observed=y)
-        # t = pm.sample(draws=100)
+        x = pm.Normal('x')
+        z = pm.Normal("z")
+        pm.Deterministic("w", x/z)
+        pm.Normal('y', observed=1)
 
     file_path = tmpdir.join("model.p")
     with open(file_path, 'wb') as buff: