quantopian/zipline — pull request #47 by twiecki (2012-12-20 17:01:13+00:00)
Title: Enhance batch_transform

This adds filtering capabilities to the batch_transform.

You can now specify
```
my_batch = BatchTransform(sids=['AAPL'], fields=['price'])
```
and it will only include those in the data panel. This is interesting for single-sid transforms (e.g. moving average), universe, and future risk.py refactoring.