[feature] Support log-uniform scale in search space definition

[gaocegege]

/kind feature

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#1205 (comment)

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[gaocegege]

/cc @sperlingxx @andreyvelich

[sperlingxx]

@gaocegege
In my opinion, we need to add additional field Distribution in FeasibleSpace. The FeasibleSpace definition could be changed to:

type ParameterDistribution string

const (
	Uniform    ParameterDistribution = "uniform"
	LogUniform ParameterDistribution = "log_uniform"
	Normal     ParameterDistribution = "normal"
	LogNormal  ParameterDistribution = "log_normal"
	Discrete   ParameterDistribution = "discrete"
)

type FeasibleSpace struct {
	Max          string                `json:"max,omitempty"`
	Min          string                `json:"min,omitempty"`
	List         []string              `json:"list,omitempty"`
	Step         string                `json:"step,omitempty"`
	Distribution ParameterDistribution `json:"distribution,omitempty"`
}

[gaocegege]

SGTM. I think it is one possible approach.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[andreyvelich]

/lifecycle frozen