use copysign for abs jet abs() implementation does not correctly handle the sign of the infinitesimal part when the value is a NaN. Define the function in terms of copysign which is the only portable way of manipulating the sign of a NaN value. Change-Id: I2f13fb1db62d35ca8b09e6bff1c05a736cb91513
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.