[mrd] missing data implemented, and plotting better

GPy/inference/latent_function_inference/var_dtc.py

@@ -202,6 +202,17 @@ class VarDTCMissingData(LatentFunctionInference):
     def set_limit(self, limit):
         self._Y.limit = limit
 
+    def __getstate__(self):
+        # has to be overridden, as Cacher objects cannot be pickled. 
+        return self._Y.limit, self._inan
+
+    def __setstate__(self, state):
+        # has to be overridden, as Cacher objects cannot be pickled. 
+        from ...util.caching import Cacher
+        self.limit = state[0]
+        self._inan = state[1]
+        self._Y = Cacher(self._subarray_computations, self.limit)
+
     def _subarray_computations(self, Y):
         if self._inan is None:
             inan = np.isnan(Y)