Jiaming Yuan
d9a47794a5
Fix CPU hist init for sparse dataset. (#4625)
* Fix CPU hist init for sparse dataset.
* Implement sparse histogram cut.
* Allow empty features.
* Fix windows build, don't use sparse in distributed environment.
* Comments.
* Smaller threshold.
* Fix windows omp.
* Fix msvc lambda capture.
* Fix MSVC macro.
* Fix MSVC initialization list.
* Fix MSVC initialization list x2.
* Preserve categorical feature behavior.
* Rename matrix to sparse cuts.
* Reuse UseGroup.
* Check for categorical data when adding cut.
Co-Authored-By: Philip Hyunsu Cho <chohyu01@cs.washington.edu>
* Sanity check.
* Fix comments.
* Fix comment.