DatasetType¶

class lsst.daf.butler.DatasetType(name, dataUnits, storageClass)¶

A named category of Datasets that defines how they are organized, related, and stored.

A concrete, final class whose instances represent DatasetTypes. DatasetType instances may be constructed without a Registry, but they must be registered via Registry.registerDatasetType() before corresponding Datasets may be added. DatasetType instances are immutable.

Parameters:

name : str: A string name for the Dataset; must correspond to the same DatasetType across all Registries.
dataUnits : iterable of str: DataUnit names that defines the DatasetRefs corresponding to this DatasetType. The input iterable is copied into a frozenset.
storageClass : StorageClass or str: Instance of a StorageClass or name of StorageClass that defines how this DatasetType is persisted.

Attributes Summary

`dataUnits`	A `frozenset` of `DataUnit` names that defines the `DatasetRef`s corresponding to this `DatasetType`.
`name`	A string name for the Dataset; must correspond to the same `DatasetType` across all Registries.
`storageClass`	`StorageClass` instance that defines how this `DatasetType` is persisted.

Methods Summary

`component`()	Component name (if defined)
`componentTypeName`(component)	Given a component name, derive the datasetTypeName of that component
`isComposite`()	Boolean indicating whether this `DatasetType` is a composite type.
`nameWithComponent`(datasetTypeName, componentName)	Form a valid DatasetTypeName from a parent and component.

Attributes Documentation

dataUnits¶: A frozenset of DataUnit names that defines the DatasetRefs corresponding to this DatasetType.

name¶: A string name for the Dataset; must correspond to the same DatasetType across all Registries.

storageClass¶: StorageClass instance that defines how this DatasetType is persisted. Note that if DatasetType was constructed with a name of a StorageClass then Butler has to be initialized before using this property.

Methods Documentation

component()¶

Component name (if defined)

Returns:	comp : `str` Name of component part of DatasetType name. `None` if this `DatasetType` is not associated with a component.

componentTypeName(component)¶

Given a component name, derive the datasetTypeName of that component

Parameters:	component : `str` Name of component
Returns:	derived : `str` Compound name of this `DatasetType` and the component.
Raises:	KeyError Requested component is not supported by this `DatasetType`.

isComposite()¶

Boolean indicating whether this DatasetType is a composite type.

Returns:	isComposite : `bool` `True` if this `DatasetType` is a composite type, `False` otherwise.

static nameWithComponent(datasetTypeName, componentName)¶

Form a valid DatasetTypeName from a parent and component.

No validation is performed.

Parameters:	datasetTypeName : `str` Base type name. componentName : `str` Name of component.
Returns:	compTypeName : `str` Name to use for component DatasetType.