Broyden-Fletcher-Goldfarb-Shanno Algorithm (BFGS)

In numerical optimization, the Broyden–Fletcher–Goldfarb–Shanno algorithm is an iterative method for solving unconstrained nonlinear optimization problems.

https://github.com/PointCloudLibrary/pcl/blob/master/registration/include/pcl/registration/bfgs.h

Saw this while trying to build LIO-SAM.