cfdm.NetCDF4Array

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class cfdm.NetCDF4Array(filename=None, address=None, dtype=None, shape=None, mask=True, unpack=True, attributes=None, storage_options=None, source=None, copy=True)

Bases: cfdm.data.mixin.indexmixin.IndexMixin, cfdm.data.mixin.netcdffilemixin.NetCDFFileMixin, cfdm.data.mixin.filearraymixin.FileArrayMixin, cfdm.data.abstract.array.Array

A netCDF array accessed with netCDF4.

New in version (cfdm): 1.7.0

Initialisation

Parameters

filename: (sequence of) str, optional

The name of the netCDF file(s) containing the array.

address: (sequence of) str or int, optional

The identity of the netCDF variable in each file defined by filename. Either a netCDF variable name or an integer netCDF variable ID.

New in version (cfdm): 1.10.1.0

dtype: numpy.dtype

The data type of the array in the netCDF file. May be None if the numpy data-type is not known (which can be the case for netCDF string types, for example).

shape: tuple

The array dimension sizes in the netCDF file.

mask: bool, optional

If True (the default) then mask by convention when reading data from disk.

A netCDF array is masked depending on the values of any of the netCDF attributes _FillValue, missing_value, _Unsigned, valid_min, valid_max, and valid_range.

New in version (cfdm): 1.8.2

unpack: bool, optional

If True (the default) then unpack by convention when reading data from disk.

A netCDF array is unpacked depending on the values of the netCDF attributes add_offset and scale_factor.

New in version (cfdm): 1.11.2.0

attributes: dict or None, optional

Provide netCDF attributes for the data as a dictionary of key/value pairs.

If attributes is None, the default, then the attributes will be set from the netCDF variable during the first __getitem__ call.

New in version (cfdm): 1.11.2.0

storage_options: dict or None, optional

Key/value pairs to be passed on to the creation of s3fs.S3FileSystem file systems to control the opening of files in S3 object stores. Ignored for files not in an S3 object store, i.e. those whose names do not start with s3:.

By default, or if None, then storage_options is taken as {}.

If the 'endpoint_url' key is not in storage_options or is not in a dictionary defined by the 'client_kwargs key (which is always the case when storage_options is None), then one will be automatically inserted for accessing an S3 file. For example, for a file name of 's3://store/data/file.nc', an 'endpoint_url' key with value 'https://store' would be created.

Parameter example:

For a file name of 's3://store/data/file.nc', the following are equivalent: None, {}, and {'endpoint_url': 'https://store'}, {'client_kwargs': {'endpoint_url': 'https://store'}}

Parameter example:

{'key': 'scaleway-api-key...', 'secret': 'scaleway-secretkey...', 'endpoint_url': 'https://s3.fr-par.scw.cloud', 'client_kwargs': {'region_name': 'fr-par'}}

New in version (cfdm): 1.11.2.0

source: optional

Convert source, which can be any type of object, to a NetCDF4Array instance.

All other parameters, apart from copy, are ignored and their values are instead inferred from source by assuming that it has the NetCDF4Array 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 NetCDF4Array instance then cfdm.NetCDF4Array(source=x) is equivalent to x.copy().

New in version (cfdm): 1.10.0.0

copy: bool, optional

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

New in version (cfdm): 1.10.0.0

missing_values: Deprecated at version 1.11.2.0

The missing value indicators defined by the netCDF variable attributes. They may now be recorded via the attributes parameter

ncvar: Deprecated at version 1.10.1.0

Use the address parameter instead.

varid: Deprecated at version 1.10.1.0

Use the address parameter instead.

group: Deprecated at version 1.10.1.0

Use the address parameter instead.

units: str or None, optional

Deprecated at version 1.11.2.0. Use the attributes parameter instead.

calendar: str or None, optional

Deprecated at version 1.11.2.0. Use the attributes parameter instead.

Inspection

Methods

get_compression_type	Returns the array’s compression type.
cfdm.NetCDF4Array.get_subspace
get_attributes	The attributes of the array.
get_missing_values	The missing value indicators from the netCDF variable.
index	The index to be applied when converting to a numpy array.

Attributes

array	Return an independent numpy array containing the data.
dtype	Data-type of the array.
ndim	Number of array dimensions.
shape	Shape of the array.
size	Number of elements in the array.
original_shape	The original shape of the data, before any subspacing.

Units

Methods

get_calendar	The calendar of the array.
get_units	The units of the array.

Attributes

Units

The Units object containing the units of the array.

File

Methods

get_address	The name of the file containing the array.
get_addresses	Return the names of the data addresses in the files.
close	Close the dataset containing the data.
open	Return a dataset file object and address.
get_filename	The name of the file containing the array.
get_filenames	Return the names of files containing the data.
get_format	The format of the files.
get_formats	Return the format of the files.
get_groups	The netCDF4 group structure of a netCDF variable.
get_mask	Whether or not to automatically mask the data.
get_unpack	Whether or not to automatically unpack the data.
get_storage_options	Return s3fs.S3FileSystem options for accessing S3 files.

Miscellaneous

copy	Return a deep copy of the array.
to_memory	Bring data on disk into memory.

Special

__getitem__

Returns a subspace of the data as a new NetCDF4Array.

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.