Remove the use of CHECK_NOTNULL. Change-Id: I6aa7dd5b44bd42807118b4b0b565d6fa8b227371
Ceres Solver is an open source C++ library for modeling and solving large, complicated optimization problems. It is a feature rich, mature and performant library which has been used in production at Google since 2010. Ceres Solver can solve two kinds of problems.
Please see ceres-solver.org for more information.