[MRG] DOC Added version information for PCA.singular_values_
@@ -223,6 +223,8 @@ class PCA(_BasePCA):
The singular values are equal to the 2-norms of the ``n_components``
variables in the lower-dimensional space.
+ .. versionadded:: 0.19
+
mean_ : array, shape (n_features,)
Per-feature empirical mean, estimated from the training set.
