Commit Graph

5 Commits

Author SHA1 Message Date
Keir Mierle 7492b0d8de Update copyright headers with new year and URL
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
2015-03-18 05:43:23 +00:00
Sameer Agarwal bcc865f81c Remove using namespace std;
For historical reasons we had a "using namespace std;" in port.h. This
is generally a bad idea. So removing it and along the way doing a bunch
of cpplint cleanup.

Change-Id: Ia125601a55ae62695e247fb0250df4c6f86c46c6
2015-01-07 14:26:53 -08:00
Sameer Agarwal a2df262441 SummarizeOrdering -> OrderingToGroupSizes
Change-Id: I6f852811c6d3812865b1da5cb94272cdf3fa4a38
2014-05-29 22:51:12 -07:00
Sameer Agarwal 36c73c26bb Stablize the schur ordering algorithm.
The schur ordering is used to construct an elimination
ordering for Schur type solvers when the user has not
supplied an elimination ordering.

The ordering algorithm does an ordered traversal of the
sparsity graph of the Hessian. The order in which this is
done used to be determined by the degree of the parameter
blocks with ties broken arbitrarily using the memory address
of the parameter blocks.

This introduced non-determinism in the solver, causing subtle
numerical differences in the value of the solution everytime
the solve was run.

This change introduces ComputeStableSchurOrdering which utilizes
a new function StableIndependentSetOrdering. The latter takes
as input an ordering of the vertices of the graph which is used
to break ties when ordering the vertice by degree. The former
constructs such an ordering by using the order in which the
parameter blocks were added to the Problem.

In this way, as long as the construction of the problem is
deterministic, the schur ordering will always be deterministic
too.

I have chosen not to delete the existing unstable implementations
of these functions as they are used by the inner iteration
minimizer.

Sometime in the near future I will clean up some of the duplicate
code and see if we can move all the code to using a stable ordering.

Change-Id: I8fbfa240d7307a2c3fe9b135f6968aa410d78780
2013-05-17 22:52:21 -07:00
Sameer Agarwal ba8d967f8c Generalization of the inner iterations algorithm.
Add automatic recursive independent set decomposition.
Clean up the naming and the API for inner iterations.

Change-Id: I3d7d6babb9756842d7367e14b7279d2df98fb724
2012-10-05 08:35:53 -07:00