cfdm.GatheredArray


class cfdm.GatheredArray(compressed_array=None, shape=None, size=None, ndim=None, compressed_dimension=None, compressed_dimensions=None, list_variable=None, source=None, copy=True)[source]

Bases: cfdm.data.abstract.compressedarray.CompressedArray

An underlying gathered array.

Compression by gathering combines axes of a multidimensional array into a new, discrete axis whilst omitting the missing values and thus reducing the number of values that need to be stored.

The information needed to uncompress the data is stored in a “list variable” that gives the indices of the required points.

See CF section 8.2 “Lossless Compression by Gathering”.

New in version (cfdm): 1.7.0

Initialisation

Parameters
compressed_array: array_like

The compressed array.

shape: tuple

The shape of the uncompressed array.

compressed_dimensions: dict

Mapping of dimensions of the compressed array to their corresponding dimensions in the uncompressed array. Compressed array dimensions that are not compressed must be omitted from the mapping.

Parameter example:

{2: (2, 3)}

New in version (cfdm): 1.10.0.0

list_variable: List

The “list variable” required to uncompress the data, identical to the data of a CF-netCDF list variable.

compressed_dimension: deprecated at version 1.10.0.0

Use the compressed_dimensions parameter instead.

source: optional

Initialise the array from the given object.

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

New in version (cfdm): 1.10.0.0

copy: bool, optional

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

New in version (cfdm): 1.10.0.0

size: int

Deprecated at version 1.10.0.0. Ignored if set.

Number of elements in the uncompressed array.

ndim: int

Deprecated at version 1.10.0.0. Ignored if set.

The number of uncompressed array dimensions

Inspection

Methods

compressed_dimensions

Mapping of compressed to uncompressed dimensions.

get_compressed_axes

Return axes that are compressed in the underlying array.

get_compressed_dimension

Returns the compressed dimension’s position in the array.

get_compression_type

Returns the array’s compression type.

get_list

Return the list variable for a compressed array.

Attributes

array

Returns a numpy array containing the uncompressed data.

compressed_array

Returns an independent numpy array with the compressed data.

dtype

The data-type of the uncompressed data.

ndim

Number of array dimensions.

shape

Shape of the uncompressed data.

size

Number of elements in the array.

Miscellaneous

Methods

copy

Return a deep copy of the array.

get_subspace

Return a subspace, defined by indices, of a numpy array.

source

Return the underlying array object.

to_memory

Bring data on disk into memory.

subarray_shapes

Create the subarray shapes along each uncompressed dimension.

subarrays

Return descriptors for every subarray.

get_Subarray

Return the Subarray class.

conformed_data

The compressed data and list variable.

Special

Methods

__array__

The numpy array interface.

__deepcopy__

Called by the copy.deepcopy function.

__getitem__

Return a subspace of the uncompressed data.

__repr__

Called by the repr built-in function.

__str__

Called by the str built-in function.

Docstring substitutions

Methods

cfdm.GatherArray._docstring_special_substitutions

cfdm.GatherArray._docstring_substitutions

cfdm.GatherArray._docstring_package_depth

cfdm.GatherArray._docstring_method_exclusions