DimensionGraph¶
-
class
lsst.daf.butler.
DimensionGraph
¶ Bases:
object
An immutable, dependency-complete collection of dimensions.
DimensionGraph
behaves in many respects like a set ofDimension
instances that maintains several special subsets and supersets of relatedDimensionElement
instances. It does not fully implement thecollections.abc.Set
interface, as its automatic expansion of dependencies would make set difference and XOR operations behave surprisingly.It also provides dict-like lookup of
DimensionElement
instances from their names.Parameters: - universe :
DimensionUniverse
The special graph of all known dimensions of which this graph will be a subset.
- dimensions : iterable of
Dimension
, optional An iterable of
Dimension
instances that must be included in the graph. All (recursive) dependencies of these dimensions will also be included. At most one ofdimensions
andnames
must be provided.- names : iterable of
str
, optional An iterable of the names of dimensiosn that must be included in the graph. All (recursive) dependencies of these dimensions will also be included. At most one of
dimensions
andnames
must be provided.- conform :
bool
, optional If
True
(default), expand to include dependencies.False
should only be used for callers that can guarantee that other arguments are already correctly expanded, and is primarily for internal use.
Notes
DimensionGraph
should be used instead of other collections in most contexts where a collection of dimensions is required and aDimensionUniverse
is available. Exceptions include cases where order matters (and is different from the consistent ordering defined by theDimensionUniverse
), or completeSet
semantics are required.Attributes Summary
names
A set of the names of all dimensions in the graph ( KeysView
).primaryKeyTraversalOrder
Return a tuple of all elements in an order allows records to be found given their primary keys, starting from only the primary keys of required dimensions ( tuple
[DimensionRecord
]).spatial
The SPATIAL
families represented by the elements in this graph.temporal
The TEMPORAL
families represented by the elements in this graph.Methods Summary
get
(name, default)Return the element with the given name. intersection
(*others)Construct a new graph containing only dimensions in all of the operands. isdisjoint
(other)Test whether the intersection of two graphs is empty. issubset
(other)Test whether all dimensions in self
are also inother
.issuperset
(other)Test whether all dimensions in other
are also inself
.union
(*others)Construct a new graph containing all dimensions in any of the operands. Attributes Documentation
-
names
¶ A set of the names of all dimensions in the graph (
KeysView
).
-
primaryKeyTraversalOrder
¶ Return a tuple of all elements in an order allows records to be found given their primary keys, starting from only the primary keys of required dimensions (
tuple
[DimensionRecord
]).Unlike the table definition/topological order (which is what DimensionUniverse.sorted gives you), when dimension A implies dimension B, dimension A appears first.
Methods Documentation
-
get
(name: str, default: Any = None) → DimensionElement¶ Return the element with the given name.
This lookup covers all
DimensionElement
instances inself.elements
, not just trueDimension
instances).
-
intersection
(*others) → lsst.daf.butler.core.dimensions._graph.DimensionGraph¶ Construct a new graph containing only dimensions in all of the operands.
-
isdisjoint
(other: lsst.daf.butler.core.dimensions._graph.DimensionGraph) → bool¶ Test whether the intersection of two graphs is empty.
Returns
True
if either operand is the empty.
-
issubset
(other: lsst.daf.butler.core.dimensions._graph.DimensionGraph) → bool¶ Test whether all dimensions in
self
are also inother
.Returns
True
ifself
is empty.
-
issuperset
(other: lsst.daf.butler.core.dimensions._graph.DimensionGraph) → bool¶ Test whether all dimensions in
other
are also inself
.Returns
True
ifother
is empty.
-
union
(*others) → lsst.daf.butler.core.dimensions._graph.DimensionGraph¶ Construct a new graph containing all dimensions in any of the operands.
The elements of the returned graph may exceed the naive union of their elements, as some
DimensionElement
instances are included in graphs whenever multiple dimensions are present, and those dependency dimensions could have been provided by different operands.
- universe :