Refactor SolverImpl.
Replace SolverImpl with
a. A minimizer specific preprocessor class.
b. A generic Solve function inside solver.cc
c. Presummarize and Postsummarize functions to handle
updates to the summary object.
The existing SolverImpl class was a mixture of the above three
things and was increasingly complicated code to follow. This change,
breaks it into its three separate constituents, with the aims of
better separation of concerns and thus better testability and
reliability.
The call to Solver::Solve() now consists of
1. Presummarize - summarize the given state of the problem and solver
options.
2. Preprocess - Setup everything that is needed to call the minimizer.
This includes, removing redundant parameter and residual blocks,
setting up the reordering for the linear solver, creating the
linear solver, evaluator, inner iteration minimizer etc.
3. Minimize.
4. Post summarize - summarize the result of the preprocessing and the
solve.
Change-Id: I80f35cfc9f2cbf78f1df4aceace27075779d8a3a
diff --git a/include/ceres/solver.h b/include/ceres/solver.h
index fdc5457..ef391a7 100644
--- a/include/ceres/solver.h
+++ b/include/ceres/solver.h
@@ -910,9 +910,15 @@
// parameter blocks.
vector<int> inner_iteration_ordering_used;
- // Type of preconditioner used for solving the trust region
- // step. Only meaningful when an iterative linear solver is used.
- PreconditionerType preconditioner_type;
+ // Type of the preconditioner requested by the user.
+ PreconditionerType preconditioner_type_given;
+
+ // Type of the preconditioner actually used. This may be different
+ // from linear_solver_type_given if Ceres determines that the
+ // problem structure is not compatible with the linear solver
+ // requested or if the linear solver requested by the user is not
+ // available.
+ PreconditionerType preconditioner_type_used;
// Type of clustering algorithm used for visibility based
// preconditioning. Only meaningful when the preconditioner_type
