madlib/madlib — pull request #133 by aojwang (2012-04-23 09:18:50+00:00)
Title: MADlib DT code refactoring and optimization

This version doesn't change the files names. However, we refactor the code so that RF and C4.5 can reuse the tree growing engine,

The main optimization includes:
1) continuous attribute optimization: Users can chosen 1~n feature's values as the split value. This will not apply to C4.5 for now. It will be used for RF.

2) The operation after found the best attributes will be done in parallel except for the create child nodes (we sequentially generate the IDs for new created child nodes).

3) Calculate the ACS set feature by feature.

4) Parallize the operations after finding the best split.