factorie/factorie — pull request #50 by lvilnis (2013-09-23 15:40:47+00:00)
Title: Bug fixes and cleanup to BP

Several fixes and a bit of cleanup:
- Chain BP wasn't getting right factor marginals for case of only 1 varying variable, which could mess up learning completely because of wrong logz (this was hard to catch because we cache logz and so noticing the bug depends on caching a wildly inaccurate logz, such as from a bias factor)
- null sets of varying variables weren't handled properly anywhere, or ever used, so they've been removed
- Max vs sum bp was handling varying neighbors differently (it was mostly doing it right in sum bp, looks like a code duplication issue)
- BPVariable marginals are now one-hots for max bp, to be consistent with factor marginals
- Removed code duplication in BPRings
- Removed some unused code and bad comments