last changes for mrd stability

GPy/likelihoods/likelihood.py

@@ -16,6 +16,7 @@ class likelihood:
     self.is_heteroscedastic : enables significant computational savings in GP
     self.precision : a scalar or vector representation of the effective target precision
     self.YYT : (optional) = np.dot(self.Y, self.Y.T) enables computational savings for D>N
+    self.V : self.precision * self.Y 
     """
     def __init__(self,data):
         raise ValueError, "this class is not to be instantiated"