The non-linear least squares solver had the ability to update the
user's parameters every iteration. Now GradientProblemSolver can
do the same.
Also a few minor Sphinx markup related cleanup to the documentation
which were found in the process of updating Sphinx on my machine
and adding the docs for this feature.
This fixes https://github.com/ceres-solver/ceres-solver/issues/246
Change-Id: Ib6b90ac22be8bfb60b14f25ad52082ba371af164
Since Ceres is moving to using GitHub for issues, and the Google
Code URL in the current copyright header will soon become invalid,
update all the headers.
Change-Id: I1fce70375d1bcf098591f07b4d8f01a5c1e0789c
1. Merge TrustRegionLoggingCallback and LineSearchLoggingCallback
into a single callback.
2. Move the callbacks into callback.h
3. Update SolverImpl to use the new callbacks.
Change-Id: I9e82173cf2b828d023d96c57d1cba17f4832aeae