fix typos. Change-Id: I9255d3c6cc0604b227ddfe065c2cdb770dceaf5c
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.