cfdm.Index¶

class cfdm.Index(properties=None, data=None, source=None, copy=True, _use_data=True)[source]

Bases: cfdm.mixin.netcdf.NetCDFVariable, cfdm.mixin.netcdf.NetCDFDimension, cfdm.mixin.netcdf.NetCDFSampleDimension, cfdm.mixin.propertiesdata.PropertiesData, cfdm.mixin.files.Files, cfdm.core.abstract.propertiesdata.PropertiesData

An index variable required to uncompress a ragged array.

A collection of features stored using an indexed ragged array combines all features along a single dimension (the sample dimension) such that the values of each feature in the collection are interleaved.

The information needed to uncompress the data is stored in an index variable that specifies the feature that each element of the sample dimension belongs to.

NetCDF interface

The netCDF variable name may be accessed with the nc_set_variable, nc_get_variable, nc_del_variable, and nc_has_variable methods.

The netCDF variable group structure may be accessed with the nc_set_variable, nc_get_variable, nc_variable_groups, nc_clear_variable_groups, and nc_set_variable_groups methods.

The name of the netCDF dimension spanned by the index variable’s data (which does not correspond to a domain axis construct) may be accessed with the nc_set_dimension, nc_get_dimension, nc_del_dimension, and nc_has_dimension methods.

The name of the netCDF sample dimension spanned by the compressed data (which does not correspond to a domain axis contract) may be accessed with the nc_set_sample_dimension, nc_get_sample_dimension, nc_del_sample_dimension, and nc_has_sample_dimension methods.

Note

The netCDF sample dimension and the netCDF dimension spanned by the index variable’s data are should be the same, unless the compressed data is an indexed contiguous ragged array, in which case they must be different.

The name of the netCDF instance dimension (that is stored in the “instance_dimension” netCDF attribute) is accessed via the corresponding domain axis construct.

New in version (cfdm): 1.7.0

Initialisation

Parameters
properties: dict, optional

Set descriptive properties. The dictionary keys are property names, with corresponding values. Ignored if the source parameter is set.

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

Parameter example:

properties={'long_name': 'which station this obs is for'}

data: data_like, optional

Set the data. Ignored if the source parameter is set.

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 instances that contain Data objects.

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

source: optional

Initialise the properties and data from those of source.

Note that if source is a Index instance then cfdm.Index(source=source) is equivalent to source.copy().

copy: bool, optional

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

Inspection¶

Methods

 dump A full description of the index variable. identity Return the canonical identity. identities Return all possible identities.

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. set_properties Set properties.

Data¶

Methods

 apply_masking Apply masking as defined by the CF conventions. del_data Remove the data. get_data Return the data. has_data Whether or not the construct has data. set_data Set the data. insert_dimension Expand the shape of the data array. squeeze Remove size one axes from the data array. transpose Permute the axes of the data array.

Attributes

 array A numpy array deep copy of the data. data Return the data. datetime_array An independent numpy array of date-time objects. dtype Data-type of the data elements. ndim The number of dimensions in the data array. shape A tuple of the data array’s dimension sizes. size The number of elements in the data array.

Miscellaneous¶

Methods

 copy Return a deep copy. creation_commands Return the commands that would create the construct. equals Whether two instances are the same. get_filenames Return the name of the file or files containing the data. cfdm.Index.original_filenames has_bounds Whether or not there are cell bounds. uncompress Uncompress the construct. to_memory Bring data on disk into memory.

NetCDF¶

Methods

 nc_del_variable Remove the netCDF variable name. nc_get_variable Return the netCDF variable name. nc_has_variable Whether the netCDF variable name has been set. nc_set_variable Set the netCDF variable name. nc_del_dimension Remove the netCDF dimension name. nc_get_dimension Return the netCDF dimension name. nc_has_dimension Whether the netCDF dimension name has been set. nc_set_dimension Set the netCDF dimension name.

Groups¶

Methods

 nc_variable_groups Return the netCDF variable group hierarchy. nc_clear_variable_groups Remove the netCDF variable group hierarchy. nc_set_variable_groups Set the netCDF variable group hierarchy. nc_dimension_groups Return the netCDF dimension group hierarchy. nc_clear_dimension_groups Remove the netCDF dimension group hierarchy. nc_set_dimension_groups Set the netCDF dimension group hierarchy.

Sample dimension¶

Methods

 nc_del_sample_dimension Remove the netCDF sample dimension name. nc_get_sample_dimension Return the netCDF sample dimension name. nc_has_sample_dimension Whether the netCDF sample dimension name has been set. nc_set_sample_dimension Set the netCDF sample dimension name. nc_sample_dimension_groups Return the netCDF sample dimension group hierarchy. nc_clear_sample_dimension_groups Remove the netCDF sample dimension group hierarchy. nc_set_sample_dimension_groups Set the netCDF sample dimension group hierarchy.

Special¶

Methods

 __deepcopy__ Called by the copy.deepcopy function. __getitem__ Return a subspace defined by indices. __repr__ Called by the repr built-in function. __str__ Called by the str built-in function.

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.