ref: 0812c121e76d28af6865b9408e2cc7e37ed0390a
parent: ddb23095686f10243af9751760b3d9889dc947ea
parent: f4fcfe3075cabc47b47db9df74720e24016ff200
author: Yunqing Wang <yunqingwang@google.com>
date: Wed May 22 09:41:04 EDT 2013
Merge "Optimize variance functions" into experimental