The Catalog Configuration File

A catalog configuration file contains the information necessary to access catalogs. The syntax of the file is as follows:

Blank lines and lines beginning with # are ignored.
Lines ending with a backslash \ are continued on the next line.
A catalog description entry is made up of keyword: value pairs, one per line.
The first keyword in every catalog entry is serv_type, which gives the type of catalog.
The order of other keywords is unimportant (many keywords are optional).
Any unknown keywords are ignored ( for compatibility with future extensions ).
Any catalog entry with an unknown serv_type is also ignored ( for compatibility ).
Many of the keywords represent query options (s ort columns, order, etc. ) that may not be supported by all catalog servers.
For all keywords requiring a list of values, the basic format is that of a Tcl list. Normally this is simply a list of words or strings in double-quotes separated by white space. However curly braces { and } may be used in place of quotes.
If a keyword's value may contain more than one list, the lists are separated by a colon ":".
If a keyword's value may contain a variable reference ( see symbol below ), the variable is expected in Tcl format. For example: $ra , ${a/b} , ${x pos} .

The syntax for each catalog entry is:

Keyword	Value
serv_type	Service type, one of: `catalog` , `archive` , `local` , `namesvr` , `imagesvr` , `directory` (see Service Types below)
long_name	Long name of catalog, suitable for displaying in a user interface.
short_name	Short name of catalog.
url	URL used to access the catalog. Variables such as %ra,%dec, etc. are expanded (see Variable Substitution in URLs below).
symbol	List indicating how to plot symbols for given column values (see Plot Symbols below).
copyright	Optional copyright notice for catalog to display in user interface.
search_cols	Optional list of column names and min and max value labels for columns that can be used to search the catalog, in the format: col1 minLabel ?maxLabel? : col2 minLabel ?maxLabel? : ... Examples: search_cols: mag "Brightest (min)" "Faintest (max)" search_cols: patch "Patch" The min and max labels are to be displayed in a user interface when entering the condition arguments for a catalog query. If two labels are given, the values are assumed to form a range (min <= x >= max) . If only a single label is specified, the search is for equality with the value enterred (x == value) .
sort_cols	Optional list of columns to sort by in the format: col1 col2 col3 ...
sort_order	Optional sort order: Set to `increasing` or `decreasing` .
show_cols	Optional list of columns to display (default: all). Besides indicating which columns to display or hide after a query, this list also indicates the order in which the user interface should present the columns. This keyword may be implemented in the user interface or optionally also in a catalog server, if it supports the option.
id_col	Column containing a unique id field (default: column 0).
ra_col	Column containing RA position (for catalogs supporting WCS, default: column 1)
dec_col	Column containing DEC position (for catalogs supporting WCS, default: column 2)
x_col	Column containing X image pixel coordinate (for catalogs not supporting WCS)
y_col	Column containing Y image pixel coordinate (for catalogs not supporting WCS)
is_tcs	The optional value may be set to 1 to indicate that the catalog is in or should be converted to TCS format. TCS catalogs have fixed column names and rules for conversion of column names from other catalogs.

Column indexes, such as ra_col , dec_col , x_col , and y_col may be set to -1 to indicate that there is no such column.

Catalog Service Types

Variable Substitution in URLs

Plot Symbols

Example Catalog Config Entry