# VOTableFile¶

class astropy.io.votable.tree.VOTableFile(ID=None, id=None, config=None, pos=None, version='1.4')[source]

Bases: astropy.io.votable.tree.Element, astropy.io.votable.tree._IDProperty, astropy.io.votable.tree._DescriptionProperty

VOTABLE element: represents an entire file.

The keyword arguments correspond to setting members of the same name, documented below.

version is settable at construction time only, since conformance tests for building the rest of the structure depend on it.

Attributes Summary

 coordinate_systems A list of coordinate system descriptions for the file. groups A list of groups, in the order they appear in the file. infos A list of informational parameters (key-value pairs) for the entire file. params A list of parameters (constant-valued columns) that apply to the entire file. resources A list of resources, in the order they appear in the file. time_systems A list of time system descriptions for the file. version The version of the VOTable specification that the file uses.

Methods Summary

 from_table(table[, table_id]) Create a VOTableFile instance from a given astropy.table.Table instance. get_coosys_by_id(self, ref[, before]) Looks up a COOSYS element by the given ID. get_field_by_id(self, ref[, before]) Looks up a FIELD element by the given ID. get_field_by_id_or_name(self, ref[, before]) Looks up a FIELD element by the given ID or name. get_fields_by_utype(self, ref[, before]) Looks up a FIELD element by the given utype and returns an iterator emitting all matches. Often, you know there is only one table in the file, and that’s all you need. get_group_by_id(self, ref[, before]) Looks up a GROUP element by the given ID. get_groups_by_utype(self, ref[, before]) Looks up a GROUP element by the given utype and returns an iterator emitting all matches. get_info_by_id(self, ref[, before]) Looks up a INFO element by the given ID. get_table_by_id(self, ref[, before]) Looks up a TABLE element by the given ID. get_table_by_index(self, idx) Get a table by its ordinal position in the file. get_tables_by_utype(self, ref[, before]) Looks up a TABLE element by the given utype, and returns an iterator emitting all matches. get_timesys_by_id(self, ref[, before]) Looks up a TIMESYS element by the given ID. get_values_by_id(self, ref[, before]) Looks up a VALUES element by the given ID. iter_coosys(self) Recursively iterate over all COOSYS elements in the VOTABLE file. Recursively iterate over all FIELD and PARAM elements in the VOTABLE file. iter_groups(self) Recursively iterate over all GROUP elements in the VOTABLE file. iter_info(self) Recursively iterate over all INFO elements in the VOTABLE file. iter_tables(self) Iterates over all tables in the VOTable file in a “flat” way, ignoring the nesting of resources etc. iter_timesys(self) Recursively iterate over all TIMESYS elements in the VOTABLE file. iter_values(self) Recursively iterate over all VALUES elements in the VOTABLE file. parse(self, iterator, config) For internal use. set_all_tables_format(self, format) Set the output storage format of all tables in the file. to_xml(self, fd[, compressed, …]) Write to an XML file.

Attributes Documentation

coordinate_systems

A list of coordinate system descriptions for the file. Must contain only CooSys objects.

groups

A list of groups, in the order they appear in the file. Only supported as a child of the VOTABLE element in VOTable 1.2 or later.

infos

A list of informational parameters (key-value pairs) for the entire file. Must only contain Info objects.

params

A list of parameters (constant-valued columns) that apply to the entire file. Must contain only Param objects.

resources

A list of resources, in the order they appear in the file. Must only contain Resource objects.

time_systems

A list of time system descriptions for the file. Must contain only TimeSys objects.

version

The version of the VOTable specification that the file uses.

Methods Documentation

classmethod from_table(table, table_id=None)[source]

Create a VOTableFile instance from a given astropy.table.Table instance.

Parameters
table_idstr, optional

Set the given ID attribute on the returned Table instance.

get_coosys_by_id(self, ref, before=None)

Looks up a COOSYS element by the given ID.

get_field_by_id(self, ref, before=None)

Looks up a FIELD element by the given ID. Used by the field’s “ref” attribute.

get_field_by_id_or_name(self, ref, before=None)

Looks up a FIELD element by the given ID or name.

get_fields_by_utype(self, ref, before=None)

Looks up a FIELD element by the given utype and returns an iterator emitting all matches.

get_first_table(self)[source]

Often, you know there is only one table in the file, and that’s all you need. This method returns that first table.

get_group_by_id(self, ref, before=None)

Looks up a GROUP element by the given ID. Used by the group’s “ref” attribute

get_groups_by_utype(self, ref, before=None)

Looks up a GROUP element by the given utype and returns an iterator emitting all matches.

get_info_by_id(self, ref, before=None)

Looks up a INFO element by the given ID.

get_table_by_id(self, ref, before=None)

Looks up a TABLE element by the given ID. Used by the table “ref” attribute.

get_table_by_index(self, idx)[source]

Get a table by its ordinal position in the file.

get_tables_by_utype(self, ref, before=None)

Looks up a TABLE element by the given utype, and returns an iterator emitting all matches.

get_timesys_by_id(self, ref, before=None)

Looks up a TIMESYS element by the given ID.

get_values_by_id(self, ref, before=None)

Looks up a VALUES element by the given ID. Used by the values “ref” attribute.

iter_coosys(self)[source]

Recursively iterate over all COOSYS elements in the VOTABLE file.

iter_fields_and_params(self)[source]

Recursively iterate over all FIELD and PARAM elements in the VOTABLE file.

iter_groups(self)[source]

Recursively iterate over all GROUP elements in the VOTABLE file.

iter_info(self)[source]

Recursively iterate over all INFO elements in the VOTABLE file.

iter_tables(self)[source]

Iterates over all tables in the VOTable file in a “flat” way, ignoring the nesting of resources etc.

iter_timesys(self)[source]

Recursively iterate over all TIMESYS elements in the VOTABLE file.

iter_values(self)[source]

Recursively iterate over all VALUES elements in the VOTABLE file.

parse(self, iterator, config)[source]

For internal use. Parse the XML content of the children of the element.

Parameters
iteratorxml iterator

An iterator over XML elements as returned by get_xml_iterator.

configdict

The configuration dictionary that affects how certain elements are read.

Returns
selfElement

Returns self as a convenience.

set_all_tables_format(self, format)[source]

Set the output storage format of all tables in the file.

to_xml(self, fd, compressed=False, tabledata_format=None, _debug_python_based_parser=False, _astropy_version=None)[source]

Write to an XML file.

Parameters
fdstr path or writable file-like object

Where to write the file.

compressedbool, optional

When True, write to a gzip-compressed file. (Default: False)

tabledata_formatstr, optional

Override the format of the table(s) data to write. Must be one of tabledata (text representation), binary or binary2. By default, use the format that was specified in each Table object as it was created or read in. See Data Serialization Formats.