error and errorSquaredNorm can optionally take in variable data

🚀 Feature

API improvement in Objective: error and errorSquaredNorm can optionally take in var_data which if passed would call update internally. Document the behavior that if var_data is passed this will update the objective.

Motivation

Facilitates usage for cases where only error needs to be queried (w/o running optimization or even updating the variables).

Pitch

Following ways to use this api after:

1. Get error on current internal values: call error without passing any var_data
2. Get error on new values w\ update to objective: call error and pass var_data
3. Get error on new values w\o update to objective: call error, pass var_data and True optional flag to not update objective

[luisenp]

Hi @jeffin07. Can you post a screenshot of the error? Also, if you make a pull request from your fork to our main branch, I can turn on CI tests and see your code and test results as well.

[luisenp]

Hi @jeffin07. That’s the correct test, yes. I noticed that the code for that test was really old, and it could be made simpler with some of the standard variables and cost function that we have now. I made a new version, which is hopefully easier to follow.

You can just add some additional code after line 281 that will tests that the functions follow the behavior we discussed above when passing other tensor values for v1_data and v2_data (and using _check_error_for_data).