Sparse pose graph is a poor name

[wohe]

The name 'sparse pose graph' is a poor choice since 'pose graph' conveys all the important information and the word 'sparse' is mostly noise: there is no other (dense/non-sparse) pose graph in Cartographer.

The name is used for a subdirectory of the code, for classes SparsePoseGraph and in the configuration as SPARSE_POSE_GRAPH and sparse_pose_graph.lua. Renaming it will break users who have to adapt their configurations.

Unless we can come up with an even better name, I propose dropping the word 'sparse'. Thoughts on this?

[ojura]

I like the name and how it's a reference to sparse pose adjustment.

Pose constraint systems, in typical robotic mapping applications,
exhibit a sparse structure of connections, since the range of
the sensor is typically limited to the vicinity of the robot.
In this paper, we develop a method to efficiently compute the
sparse matrix from the constraint graph, and use direct sparse
linear methods to solve it.

If you wanted to convey this, a more accurate name would be e.g. 'sparsely optimised pose graph' or 'SPA pose graph'. But that would be noise :-)

[cschuet]

I would also argue that since sparse pose graph is a known concept in SLAM it is useful to conserve it in the name.

[cschuet]

All further discussion on the RFC.