Corrected v2 missing print brackets. Added test code for new model and util

GPy/testing/model_tests.py

@@ -405,6 +405,24 @@ class MiscTests(unittest.TestCase):
         warp_m.plot()
         warp_f.plot(X.min()-10, X.max()+10)
         plt.show()
+        
+    def test_offset_regression(self):
+        #Tests GPy.models.GPOffsetRegression. Using two small time series
+        #from a sine wave, we confirm the algorithm determines that the
+        #likelihood is maximised when the offset hyperparameter is approximately
+        #equal to the actual offset in X between the two time series.
+        offset = 3
+        X1 = np.arange(0,50,5.0)[:,None]
+        X2 = np.arange(0+offset,50+offset,5.0)[:,None]
+        X = np.vstack([X1,X2])
+        ind = np.vstack([np.zeros([10,1]),np.ones([10,1])])
+        X = np.hstack([X,ind])
+        Y = np.sin((X[0:10,0])/30.0)[:,None]
+        Y = np.vstack([Y,Y])
+
+        m = GPy.models.GPOffsetRegression(X,Y)
+        m.optimize()
+        assert np.abs(m.offset[0]-offset)<0.1, "GPOffsetRegression model failing to estimate correct offset."