stan-dev / stan-dev/rstan

optimizing needs informative error message if theta_tilde not returned

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Description

For optimizing, when this line

https://github.com/stan-dev/rstan/blob/322a3e8e0567e775dde97c80986463e46649e59b/rstan/rstan/R/stanmodel-class.R#L369

is executed, if is.matrix(R <- try(chol(-H))) is FALSE (i.e. if there's an error computing chol(-H)) then an error is thrown about that but there is no message telling the user that because of this no draws theta_tilde from the MVN will be returned. We should have such a message/warning.

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Research direction

Inspect rstan/rstan/R/stanmodel-class.R at the linked line in optimizing, focusing on the branch where chol(-H) fails and theta_tilde is not returned. Reproduce that path and check how the existing error is surfaced; done means the resulting message or warning also tells users that no theta_tilde draws from the MVN will be returned.

Written by the indexing model from the issue text.

Assessment

Tech stack
r
Domain
data
Issue type
Bug
Difficulty
2/5
Estimated time
1-3 hours
Activity status
Stale
Clarity
Clearly specified
Newbie friendliness
42/100

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