cfdm.core.CellConnectivity

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class cfdm.core.CellConnectivity(connectivity=None, properties=None, data=None, source=None, copy=True, _use_data=True)

Bases: cfdm.core.abstract.topology.Topology

A cell connectivity construct of the CF data model.

A cell connectivity construct defines explicitly how cells arranged in two or three dimensions in real space but indexed by a single domain (discrete) axis are connected. Connectivity can only be provided when the domain axis construct also has a domain topology construct, and two cells can only be connected if they also have a topological relationship. For instance, the connectivity of two-dimensional face cells could be characterised by whether or not they have shared edges, where the edges are defined by connected nodes of the domain topology construct.

The cell connectivity construct consists of an array recording the connectivity, and properties to describe the data. There must be a property indicating the condition by which the connectivity is derived from the domain topology. The array spans the domain axis construct with the addition of a ragged dimension. For each cell, the first element along the ragged dimension contains the unique identity of the cell, and the following elements contain in arbitrary order the identities of all the other cells to which the cell is connected. Note that the connectivity array for point cells is, by definition, equivalent to the array of the domain topology construct.

When cell connectivity constructs are present they are considered to be definitive and must be used in preference to the connectivities implied by inspection of any other constructs, apart from the domain topology construct, which are not guaranteed to be the same.

See CF Appendix I “The CF Data Model”.

New in version (cfdm): 1.11.0.0

Initialisation

Parameters

connectivity: str, optional

The connectivity type describes a characteristic of inter-cell connectivity defined by the domain topology construct. It may take any value, but the following values are standardised: 'node'``(edge or face cells connected by one or more shared nodes) and ``'edge' (face cells connected by one or more shared edges).

properties: dict, optional

Set descriptive properties. The dictionary keys are property names, with corresponding values.

Properties may also be set after initialisation with the set_properties and set_property methods.

Parameter example:

properties={'long_name': 'face-face connectivity'}

data: data_like, optional

Set the data.

A data_like object is any object that can be converted to a Data object, i.e. numpy array_like objects, Data objects, and cfdm.core instances that contain Data objects.

The data also may be set after initialisation with the set_data method.

source: optional

Convert source, which can be any type of object, to a CellConnectivity instance.

All other parameters, apart from copy, are ignored and their values are instead inferred from source by assuming that it has the CellConnectivity API. Any parameters that can not be retrieved from source in this way are assumed to have their default value.

Note that if x is also a CellConnectivity instance then cfdm.core.CellConnectivity(source=x) is equivalent to x.copy().

copy: bool, optional

If True (the default) then deep copy the input parameters prior to initialisation. By default the parameters are not deep copied.

Inspection

Attributes

construct_type

Return a description of the construct type.

Properties

Methods

del_property	Remove a property.
get_property	Return a property.
has_property	Whether a property has been set.
set_property	Set a property.
properties	Return all properties.
clear_properties	Remove all properties.
del_properties	Remove properties.
set_properties	Set properties.

Topology

Methods

del_connectivity	Remove the connectivity.
get_connectivity	Return the connectivity type.
has_connectivity	Whether the connectivity type has been set.
set_connectivity	Set the connectivity type.

Data

Methods

del_data	Remove the data.
get_data	Return the data.
has_data	Whether or not the construct has data.
set_data	Set the data.

Attributes

data	The data.
dtype	Data-type of the data elements.
ndim	The number of data dimensions.
shape	A tuple of the data array’s dimension sizes.
size	The number elements in the data.

Bounds

Methods

has_bounds

Whether or not there are cell bounds.

Miscellaneous

Methods

copy	Return a deep copy.

Special

Methods

__deepcopy__	Called by the copy.deepcopy function.
__repr__	Return repr(self).
__str__	Return str(self).

Docstring substitutions

Methods

_docstring_special_substitutions	Return the special docstring substitutions.
_docstring_substitutions	Returns the substitutions that apply to methods of the class.
_docstring_package_depth	Returns the class {{package}} substitutions package depth.
_docstring_method_exclusions	Returns method names excluded in the class substitutions.