[Tune] Do not warn in BayesOpt w/ Uniform sampler

[Yard1]

Signed-off-by: Antoni Baum [email protected]

Why are these changes needed?

BayesOpt supports only uniform sampling, but we erroneously warn when the Uniform sampler is used (as opposed to no sampler at all). This PR fixes that issue.

Related issue number

Closes #30338

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[justinvyu]

Do we clarify in the docs what can be passed into the search space when using BayesOptSearch?

[Yard1]

@justinvyu We indirectly mention that by stating the space has to be continuous - we don't really call this out specifically in any searcher, really. We should improve that in a future PR!

[justinvyu]

Does the check need to also include other continuous spaces (LogUniform)? Maybe I am missing something here though.

[Yard1]

No, this searcher only supports basic uniform sampling:

            if isinstance(domain, Float):
                if domain.sampler is not None and not isinstance(
                    domain.sampler, Uniform
                ):
                    logger.warning(
                        "BayesOpt does not support specific sampling methods. "
                        "The {} sampler will be dropped.".format(sampler)
                    )
                return (domain.lower, domain.upper) # <- BayesOpt domain definition allowing only for uniform sampling

[xwjiang2010]

Just curious, why is that BayesOpt only supports uniform sampler?

btw, will this page be updated? https://docs.ray.io/en/latest/tune/examples/bayesopt_example.html

It has the wrong warning..

[Yard1]

It only supports the uniform sampler as that's what's the underlying library supports.

Removed the warning from example!

[krfricke]

Thanks!