cf.Field

class cf.Field(properties={}, domain=None, data=None, attributes={}, flags=None, ancillary_variables=None, dimensions=None, finalize=True)

Bases: cf.variable.Variable

A field construct according to the CF data model.

A field is a container for a data array and metadata comprising properties to describe the physical nature of the data and a coordinate system (called a domain) which describes the positions of each element of the data array.

The field’s domain may contain coordinates and cell measures (which themselves contain data arrays and properties to describe them) and transforms to further describe existing coordinates or to describe how new coordinates may be computed.

All components of a field are optional.

Miscellaneous

Field objects are picklable.

Initialization

Parameters :

properties : dict, optional

Provide the new field with CF properties from the dictionary’s key/value pairs. Values are deep copied.

data : Data, optional

Provide the new field with an N-dimensional data array in a cf.Data object. The array is deep copied.

domain : Domain, optional

Provide the new field with a coordinate system in a cf.Domain object. The domain is deep copied. By default an empty domain is created.

attributes : dict, optional

Provide the new field with attributes from the dictionary’s key/value pairs. Values are deep copied.

flags : Flags, optional

Provide the new field with self-describing flag values in a cf.Flags object. The flags are deep copied.

ancillary_variables : AncillaryVariables, optional

Provide the new field with ancillary variable fields in a cf.AncillaryVariables object. The ancillary variables are deep copied.

dimensions : sequence of str, optional

A list of dimension identifiers ('dimN'), stating the dimensions, in order, of field’s data array. By default these dimension identifiers will be the sequence of consecutive dimension identifiers 'dim0' up to 'dimM', where M is the number of dimensions of the data array, or an empty sequence if the data array is a scalar.

If the field’s domain defines dimensions, then their identifiers and sizes must correspond to those of the field’s data array. Otherwise, new dimensions will be created in the field’s domain.

If the field’s domain has any of the data array’s dimensions, then their sizes must correspond to those of the field’s data array.

finalize : bool, optional

If False then do not finalize the field with its finalize method. By default the field is finalized.

Field CF Properties

add_offset	The add_offset CF property.
calendar	The calendar CF property.
cell_methods	The CellMethods object containing the CF cell methods of the data array.
comment	The comment CF property.
Conventions	The Conventions CF property.
_FillValue	The _FillValue CF property.
flag_masks	The flag_masks CF property.
flag_meanings	The flag_meanings CF property.
flag_values	The flag_values CF property.
history	The history CF property.
institution	The institution CF property.
leap_month	The leap_month CF property.
leap_year	The leap_year CF property.
long_name	The long_name CF property.
missing_value	The missing_value CF property.
month_lengths	The month_lengths CF property.
references	The references CF property.
scale_factor	The scale_factor CF property.
source	The source CF property.
standard_error_multiplier	The standard_error_multiplier CF property.
standard_name	The standard_name CF property.
title	The title CF property.
units	The units CF property.
valid_max	The valid_max CF property.
valid_min	The valid_min CF property.
valid_range	The valid_range CF property.

Field data attributes

array	A numpy array deep copy of the data array.
Data	The cf.Data object containing the data array.
dtype	The numpy data type of the data array.
_FillValue	The _FillValue CF property.
first_datum	The first element of the data array.
hardmask	Whether the mask is hard (True) or soft (False).
isscalar	True if and only if the data array is a scalar array.
last_datum	The last element of the data array.
mask	A field containing the mask of the data array.
ndim	Number of dimensions in the data array.
shape	Tuple of the data array’s dimension sizes.
size	Number of elements in the data array.
Units	The Units object containing the units of the data array.
varray	A numpy array view of the data array.

Field attributes

ancillary_variables	An AncillaryVariables object containing CF ancillary data.
domain	The Domain object containing the coordinate system (domain).
Flags	A Flags object containing self-describing CF flag values.
id	A definitive identity for the variable.
properties	A dictionary of the CF properties.
subspace	Return a new object which in turn may return a subspace of the field.

Field methods

binary_mask	Return a binary missing data mask of the data array.
chunk	Partition the field in place for LAMA functionality.
clip	Clip (limit) the values in the data array in place.
close	Close all files referenced by the field.
coord	Return a coordinate of the domain.
copy	Return a deep copy.
cos	Take the trigonometric cosine of the data array in place.
delprop	Delete a CF property.
dump	Return a string containing a description of the field.
equals	True if two fields are logically equal, False otherwise.
equivalent	True if and only if two fields are logically equivalent.
equivalent_data	Equivelence is defined as both fields having the same data arrays after accounting for different but equivalent units, size one dimensions, different dimension directions and different dimension orders.
expand_dims	Expand the shape of the data array in place.
finalize	Finalize a newly created field.
flip	Flip dimensions of the data array and domain in place.
getprop	Get a CF property.
hasprop	Return True if the variable has a CF property.
identity	Return the variable’s identity.
indices	Return the indices to the data array which correspond to coordinate values.
insert_data	Insert a new data array into the field in place, preserving internal consistency.
match	Determine whether or not a field matches the given conditions.
name	Return a name for the variable.
override_units	Override the data array units in place.
remove_data	Remove the fields’s data array in-place, preserving internal consistency.
select	Return the field if it matches the given conditions.
setitem	Set selected elements of the data array in place.
setmask	Set selected elements of the data array’s mask in place.
setprop	Set a CF property.
sin	Take the trigonometric sine of the data in place.
squeeze	Remove size 1 dimensions from the field’s data array in place.
transpose	Permute the dimensions of the data array in place.
unsqueeze	Insert size 1 dimensions from the field’s domain into its data array in place.

Field arithmetic and comparison operations

See the section on arithmetic and comparison operations.