The string appended to the server URL in the configuration file and which defines the type of queries supported by the catalogue has a format something like:
ra=%ra&dec=%dec&radius=%r2
It consists of simple characters and `tokens'. The tokens start with a `%' character. When GAIA makes a query the tokens are replaced with values which correspond to the individual query and the resulting string is sent to the server. For example, tokens in the above string might be susbstituted to yield:
ra=10:30:00&dec=-30:30.0&radius=3
Obviously the format of the query string appended to the URL in the configuration file must correspond to that expected by the server. Various standard tokens can be included in the query string. Some common ones are:
For a complete list see Section
.
Writing Catalogue and Image Servers for GAIA and CURSA