new($str_or_ref, %options)
get_ID
set_ID($id)
get_epoch
set_epoch($epoch)
get_equinox
set_equinox($equinox)
get_system
set_system($system)
get
set($str)
VOTABLE::COOSYS - VOTABLE COOSYS XML element class
use VOTABLE::COOSYS;
This class implements the COOSYS
element from the VOTABLE
DTD. This element is used to store coordinate system information
(hence the element tag name). Other elements of a VOTABLE
document,
such as FIELD
elements for coordinates, typically reference a
COOSYS
element (using the value of the ID
attribute of the
COOSYS
element) to indicate the coordinate system which should be
used to interpret the coordinates.
The COOSYS
element is a Tier 0 element, and is described by the
following excerpt from the VOTABLE
1.0 DTD:
<!ELEMENT COOSYS (#PCDATA)> <!ATTLIST COOSYS ID ID #IMPLIED equinox CDATA #IMPLIED epoch CDATA #IMPLIED system (eq_FK4 | eq_FK5 | ICRS | ecl_FK4 | ecl_FK5 | galactic | supergalactic | xy | barycentric | geo_app) "eq_FK5" >
new($str_or_ref, %options)
Create a new VOTABLE::COOSYS
object, and return a reference to
it. If the first argument ($str_or_ref
) is a string, it is used as
the initial #PCDATA
content of the COOSYS
element. If the first
argument is a reference to a XML::DOM::Element
object, that object
is used to initialize the new COOSYS
element (implicitly assuming
that the XML::DOM::Element
object contains a valid COOSYS
element). The %options
hash is used to set the attributes of the
new element. If the first argument is missing or undefined, or an
empty string, create and return an empty VOTABLE::COOSYS
object. Return undef
if an error occurs.
get_ID
Return the value of the ID
attribute. Return undef
if the
attribute has not been set, or an error occurs.
set_ID($id)
Set the value of the ID
attribute to the specified value. Use
undef
as the argument to clear any existing value of the
attribute. Return the new value of the attribute on success, or
undef
if an error occurs.
get_epoch
Return the value of the epoch
attribute. Return undef
if the
attribute has not been set, or an error occurs.
set_epoch($epoch)
Set the value of the epoch
attribute to the specified value. Use
undef
as the argument to clear any existing value of the
attribute. Return the new value of the attribute on success, or
undef
if an error occurs.
get_equinox
Return the value of the equinox
attribute. Return undef
if the
attribute has not been set, or an error occurs.
set_equinox($equinox)
Set the value of the equinox
attribute to the specified value. Use
undef
as the argument to clear any existing value of the
attribute. Return the new value of the attribute on success, or
undef
if an error occurs.
get_system
Return the value of the system
attribute. Return the default value
(eq_FK5
) if the attribute has not been set. Return undef
if an
error occurs.
set_system($system)
Set the value of the system
attribute to the specified value. The
new value is checked for correctness against the list of allowed
values. Use undef
as the argument to clear any existing value of
the attribute. Return the new value of the attribute on success, or
undef
if an error occurs.
get
Return a string containing the #PCDATA
content of the COOSYS
element. Return undef
if the element has no #PCDATA
content, or
an error occurs.
set($str)
Set the #PCDATA
content of the COOSYS
element to the specified
string. Use undef
as the argument to clear any existing value of
the text. Return the string on success, or undef
if an error
occurs.
_
') are for
internal use only, and should not be used outside of the VOTABLE
class hierarchy.
get_XXX
and set_XXX
accessors for attributes
and elements are derived directly from the names of the attributes or
elements, with the attribute or element name replacing
XXX
. Attribute and element names containing embedded hyphens
('-
') use accessors where the hyphen is mapped to an underscore
('_
') in the name of the accessor method. This is a necessity,
since the hyphen is not a valid name character in Perl.
VOTABLE
object always has an underlying XML::DOM::Element
object. As long as the internal structure is manipulated only by the
publicly-available methods, this should be a safe assumption. If a
method detects an aberrant case, a warning message is printed (using
the Carp::carp
subroutine), and the method fails.
XML::DOM
methods always
succeed. If a method detects an aberrant case, a warning message is
printed (using the Carp::carp
subroutine), and the method fails.
set_XXX
accessors do not perform validation of the
new attribute values. The exceptions are the accessors for attributes
with enumerated values; the new value is checked against the list of
acceptable values, as defined in the DTD.
VOTABLE
, VOTABLE::DEFINITIONS
, VOTABLE::RESOURCE
Eric Winter, NASA GSFC (elwinter@milkyway.gsfc.nasa.gov)
$Id: COOSYS.pm,v 1.1.1.11 2002/06/09 21:13:08 elwinter Exp $