cfdm.Datum


class cfdm.Datum(parameters=None, source=None, copy=True)[source]

Bases: cfdm.mixin.parameters.Parameters, cfdm.mixin.netcdf.NetCDFVariable, cfdm.core.datum.Datum

A datum component of a CF data model coordinate reference.

A datum is a complete or partial definition of the zeroes of the dimension and auxiliary coordinate constructs which define a coordinate system.

The datum may contain the definition of a geophysical surface which corresponds to the zero of a vertical coordinate construct, and this may be required for both horizontal and vertical coordinate systems.

Elements of the datum not specified may be implied by the properties of the dimension and auxiliary coordinate constructs referenced by the CoordinateReference instance that contains the datum.

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.

New in version (cfdm): 1.7.0

Initialisation

Parameters
parameters: dict, optional

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

Parameters may also be set after initialisation with the set_parameters and set_parameter methods.

Parameter example:

parameters={'earth_radius': 6371007.}

source: optional

Initialise the parameters from those of source.

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

copy: bool, optional

If False then do not deep copy input parameters prior to initialisation. By default arguments are deep copied.

Parameter terms

Methods

del_parameter

Delete a parameter.

get_parameter

Get a parameter value.

has_parameter

Whether a parameter has been set.

set_parameter

Set a parameter-valued term.

parameters

Return all parameters.

set_parameters

Set parameters.

clear_parameters

Remove all parameters.

Miscellaneous

Methods

copy

Return a deep copy.

equals

Whether two instances are the same.

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.

Groups

Methods

nc_variable_groups

Return the netCDF variable group hierarchy.

nc_set_variable_groups

Set the netCDF variable group hierarchy.

nc_clear_variable_groups

Remove the netCDF variable group hierarchy.

Special

Methods

__bool__

Called by the bool built-in function.

__deepcopy__

Called by the copy.deepcopy function.

cfdm.Datum.__nonzero__

__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.