GradientProblemSolver::Options does not support update_state_every_iteration

[bchretien]

While implementing a callback for GradientProblemSolver, I realized that update_state_every_iteration is not supported for that kind of solver. Yet, GradientProblemSolver::Options::callbacks's documentation hints at the contrary (here):

// Callbacks are executed in the order that they are specified in
// this vector. By default, parameter blocks are updated only at
// the end of the optimization, i.e when the Minimizer
// terminates. This behaviour is controlled by
// update_state_every_variable. If the user wishes to have access
// to the update parameter blocks when his/her callbacks are
// executed, then set update_state_every_iteration to true.

Are there any plans to support this option, or am I missing something? Otherwise, the documentation should probably be updated. Also, update_state_every_variable is referenced, but I'm assuming this is a typo/legacy name for update_state_every_iteration (it is also present in some other parts of the documentation).

This was tested with Ceres 1.12.0.

[sandwichmaker]

@bchretien thanks for reporting this, yes this is a bug in gradientproblemsolver, even though the underlying machinery actually supports this. You can either submit a patch or I can look into it soonish.

[bchretien]

@sandwichmaker thanks for the quick reply, I probably won't have the time to work on a patch during the next few weeks, but I'll keep you posted if that changes.

[bchretien]

I think I solved the issue (cf. this). I'll forward this to Gerrit when I find the time.

[sandwichmaker]

@bchretien that CL looks pretty good. Please do consider sending it to gerrit, I will review as soon as I can.

[sandwichmaker]

@bchretien gentle ping :)

[aecins]

@bchretien another gentle ping. Ran into this issue this week. It would be really great to see per iteration updates with the gradient solver.

[keir]

@bchretien Would happy review your patch in Gerrit; can you please push it over there so we can get it submitted? Due to the CLA issue we can't accept GitHub pull requests (and we want to keep our review history centralized).

[brentmorgan1987]

Is there a quick fix to see my solution per every iteration? This is needed for me :)....
I could technically write the solution for every Evaluate() call but it would probably slow it down, compared to a "real" fix. Thanks,

Best,
Brent

[sandwichmaker]

https://ceres-solver-review.googlesource.com/c/ceres-solver/+/11780 is out for review.

[brentmorgan1987]

I implemented the changes. What am I supposed to see? I do not see any changes in the stdout.

I set the
update_state_every_iteration = true
in gradient_problem_solver.h

Best,
Brent