- Increase precision of numeric values output in error messages to
allow for easier debugging.
- Ensure termination after Wolfe search bracketing phase if bracket
width has been shrunk to below tolerance.
- Cleaned up return value for BracketingPhase(), now false iff
optimisation should stop, true otherwise.
- Fix bug whereby we would mark a step size as satisfying the Wolfe
conditions when it did not due to numerical issues in the cost
function.
- Adding explanation of a subtlety in which a zoom could still be
acceptably invoked with bracket_low.f > bracket_high.f.
- Replacing hard check of a pre-condition of ZoomPhase() with a
conditional return if not satisfied to address issue whereby a
bracket could be incorrectly identified due to inconsistent values
& gradients returned from the cost function.
- Adding missing check for step size validity in line search minimizer.
- Adding ToDebugString() for FunctionSample.
Change-Id: Iad98e635749877f80c079ebad126bf022d82232d
The original visibility based preconditioning paper and
implementation only used the canonical views algorithm.
This algorithm for large dense graphs can be particularly
expensive. As its worst case complexity is cubic in size
of the graph.
Further, for many uses the SCHUR_JACOBI preconditioner
was both effective enough while being cheap. It however
suffers from a fatal flaw. If the camera parameter blocks
are split between two or more parameter blocks, e.g,
extrinsics and intrinsics. The preconditioner because
it is block diagonal will not capture the interactions
between them.
Using CLUSTER_JACOBI or CLUSTER_TRIDIAGONAL will fix
this problem but as mentioned above this can be quite
expensive depending on the problem.
This change extends the visibility based preconditioner
to allow for multiple clustering algorithms. And adds
a simple thresholded single linkage clustering algorithm
which allows you to construct versions of CLUSTER_JACOBI
and CLUSTER_TRIDIAGONAL preconditioners that are cheap
to construct and are more effective than SCHUR_JACOBI.
Currently the constants controlling the threshold above
which edges are considered in the single linkage algorithm
are not exposed. This would be done in a future change.
Change-Id: I7ddc36790943f24b19c7f08b10694ae9a822f5c9
1. When a LAPACK implementation is present, then
DENSE_QR, DENSE_NORMAL_CHOLESKY and DENSE_SCHUR
can use it for doing dense linear algebra operations.
2. The user can switch dense linear algebra libraries
by setting Solver::Options::dense_linear_algebra_library_type.
3. Solver::Options::sparse_linear_algebra_library is now
Solver::Options::sparse_linear_algebra_library_type to be consistent
with all the other enums in Solver::Options.
4. Updated documentation as well as Solver::Summary::FullReport
to reflect these changes.
Change-Id: I5ab930bc15e90906b648bc399b551e6bd5d6498f
Also
1. Remove an inadvertent LOG(INFO) from trust_region_minimizer.cc
2. Refactor some of the code in FullReport to reduce duplication
across line search and trust region minimizers.
3. Consistent capitalization.
Change-Id: I9078b1704efab23d2858530636f524e60c7d9016
Here is an example report, obtained by running:
bin/Debug/bundle_adjuster \
--input=../ceres-solver/data/problem-16-22106-pre.txt \
--linear_solver=iterative_schur \
--num_iterations=1 \
--alsologtostderr \
--use_local_parameterization \
--use_quaternions
Note that effective parameters is less than parameters by 16, which is the
number of cameras. In this case the local parameterization has a 3 dimensional
tangent space for the 4-dimensional quaternions.
Ceres Solver Report
-------------------
Original Reduced
Parameter blocks 22138 22138
Parameters 66478 66478
Effective parameters 66462 66462
Residual blocks 83718 83718
Residual 167436 167436
Minimizer TRUST_REGION
Trust Region Strategy LEVENBERG_MARQUARDT
Given Used
Linear solver ITERATIVE_SCHUR ITERATIVE_SCHUR
Preconditioner JACOBI JACOBI
Threads: 1 1
Linear solver threads 1 1
Linear solver ordering AUTOMATIC 22106, 32
Cost:
Initial 4.185660e+06
Final 7.221647e+04
Change 4.113443e+06
Number of iterations:
Successful 1
Unsuccessful 0
Total 1
Time (in seconds):
Preprocessor 0.697
Residual Evaluations 0.063
Jacobian Evaluations 27.608
Linear Solver 13.360
Minimizer 43.973
Postprocessor 0.004
Total 44.756
Termination: NO_CONVERGENCE
Change-Id: I6b6b8ac24f71bd187e67d95651290917642be74f
1. Added a Preconditioner interface.
2. SCHUR_JACOBI is now its own class and is independent of
SuiteSparse.
Change-Id: Id912ab19cf3736e61d1b90ddaf5bfba33e877ec4
1. Add an ExecutionSummary object to record execution
information about Ceres objects.
2. Add an EventLogger object to log events in a function call.
3. Add a ScopedExecutionTimer object to log times in ExecutionSummary.
4. Instrument ProgramEvaluator and all the linear solvers
to report their timing statistics.
5. Connect the timing statistics to Summary::FullReport.
6. Add high precision timer on unix systems using
gettimeofday() call.
7. Various minor clean ups all around.
Change-Id: I5e09804b730b09535484124be7dbc1c58eccd1d4
Add automatic recursive independent set decomposition.
Clean up the naming and the API for inner iterations.
Change-Id: I3d7d6babb9756842d7367e14b7279d2df98fb724
Remove the old ordering API, and modify solver_impl.cc
to use the new API everywhere.
In the process also clean up the linear solver instantion
logic in solver_impl.cc a bit too.
Change-Id: Ia66898abc7f622070b184b21fce8cc6140c4cebf
This fixes the bug introduced in a previous commit,
and adds a test to check that constant parameter
blocks work as expected.
This also refactors the Solver/SolverImpl split so
that SolverImpl is no longer a friend of Problem;
instead, Solver is. This makes it possible to
verify the invariant on parameter block states in
the unit test, and is a more symmetric design
anyway.
Bug: 51
Change-Id: Id503f5b526cfb8bc24aae3aaad2e414b14063d78
1. Document the use of dogleg and a general discussion of
trust region methods.
2. Added a TBD section on compiler/linker flags.
3. Summary::FullReport now prints out sparse_linear_algebra_library
and trust_region_strategy_type.
Change-Id: I01f680070d510715900f345364855689005d54bb
1. A new dogleg trust region strategy.
2. Consistent naming of all variables taking and reporting
time. Also all are doubles now.
3. Enum to stringification routines.
4. bundle_adjuster.cc accepts max solver time and trust_region_strategy.
5. Time accounting is pushed into solver_impl.cc and there is now
postprocessing time accounted for explicitly.
6. IterationCallback now has cumulative time.
7. LoggingCallback logs per iteration and cumulative time.
8. TrustRegionStrategy now allows for Invalid steps to be indicated
explicitly.
9. Trust region minimizer actually terminates on max_solver_time.
Change-Id: I7e3b82c8beebc17b6b355ea46ddd280754a2d8b2
1. New TrustRegionMinimizer and basic tests for it.
2. New TrustRegionStrategy interface.
3. New LevenbergMarquardtStrategy and tests for it.
4. Updates to SolverImpl to reflect this.
5. Changes to Solver::Options and IterationSummary related to this.
6. Deleted levenberg_marquardt.cc/h/_test.cc
Change-Id: I6c1d1a7c774f014856f9f26263a830aa886e1400
- Rename BlockDiagonalPreconditioner to BlockJacobiPreconditioner
- Include the diagonal in the block jacobi preconditioner.
- Better flag help for eta.
- Enable test for CGNR
- Rename CONJUGATE_GRADIENTS to CGNR.
- etc.
This adds a new LinearOperator which implements symmetric
products of a matrix, and a new CGNR solver to leverage
CG to directly solve the normal equations. This also
includes a block diagonal preconditioner. In experiments
on problem-16, the non-preconditioned version is about
1/5 the speed of SPARSE_SCHUR, and the preconditioned
version using block cholesky is about 20% slower than
SPARSE_SCHUR.
Sameer Agarwal