# cf.Field.auxiliary_coordinate¶

Field.auxiliary_coordinate(identity, default=ValueError(), key=False)[source]

Return an auxiliary coordinate construct, or its key.

New in version 3.0.0.

Parameters: identity: Select the auxiliary coordinate construct by one of: The identity or key of an auxiliary coordinate construct. The identity or key of a domain axis construct that is spanned by a unique 1-d auxiliary coordinate construct’s data. The position, in the field construct’s data, of a domain axis construct that is spanned by a unique 1-d auxiliary coordinate construct’s data. A construct identity is specified by a string (e.g. 'latitude', 'long_name=time', 'ncvar%lat', etc.); a Query object (e.g. cf.eq('longitude')); or a compiled regular expression (e.g. re.compile('^atmosphere')) that selects the relevant constructs whose identities match via re.search. A construct has a number of identities, and is selected if any of them match any of those provided. A construct’s identities are those returned by its identities method. In the following example, the construct x has six identities: >>> x.identities() ['time', 'long_name=Time', 'foo=bar', 'standard_name=time', 'ncvar%t', T']  A construct key may optionally have the 'key%' prefix. For example 'auxiliarycoordinate2' and 'key%auxiliarycoordinate2' are both acceptable keys. A position of a domain axis construct in the field construct’s data is specified by an integer index. Note that in the output of a print call or dump method, a construct is always described by one of its identities, and so this description may always be used as an identity argument. Parameter example: identity='Y' Parameter example: identity='latitude' Parameter example: identity='long_name=Latitude' Parameter example: identity='auxiliarycoordinate1' Parameter example: identity='domainaxis2' Parameter example: identity='ncdim%y' Parameter example: identity=0 key: bool, optional If True then return the selected construct key. By default the construct itself is returned. default: optional Return the value of the default parameter if a construct can not be found. If set to an Exception instance then it will be raised instead. AuxiliaryCoordinate or str The selected auxiliary coordinate construct, or its key.

Examples:

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