/database                                                 September 2002

This subdirectory contains the IDL procedures, mostly written by Don Lindler,
(ACC/Goddard) to create and access an IDL database.   These database procedures
are currently used by the HST-ACS, HST-STIS, HST-WFC3 and SOHO  science teams. 
The LaTex file database.tex in the /text directory describes  the use of the
database procedures with an emphasis on astronomical  applications.     Further
information on the database software is available  in Chapter 3 and Appendix J
of "A User's Guide to the GHRS Software" available as a postscript file or as
.html help from  http://hrssun.gsfc.nasa.gov/daf/sw_docs.html

The database procedures require the non-standard system variables
!PRIV, !TEXTOUT, and !TEXTUNIT.   These can be added to the IDL session 
by using the procedure ASTROLIB.

Sample astronomical catalogs, formatted as IDL databases, are available in the
/zdbase directory.   These include the Yale Bright Star Catalog, the 
RC3 Galaxy catalog, and a catalog of HST observations.

Very large (> 15 million entries) databases may require the use of 64 bit
integers - and at least V5.2 -- internally.     Updated versions of DBINDEX,
DBINDEX_DBF, DBFIND_SORT, and DBEXT_IND are available in
ftp://idlastro.gsfc.nasa.gov/pub/v53.

24-Sep-2002:  DBTARGET() - Find database entries within specified radius of 
                     supplied astronomical target name.
                   
20-Sep-2002: DBPRINT - New /AdjustFormat will adjust the format length for 
                string items to the maximum length for the entries to be 
                printed.    


23-Jul-2001: DBCREATE, DBFIND, DBFIND_SORT, DBXVAL, DBINDEX_BLK, DBBUILD -
             Now allow user to specify items with 64 bit or unsigned integer
             datatypes.

2-Dec-2000:  DBINDEX, DBEXT_IND - Now allow multiple-valued index items
             Minor updates to database.tex file

17-Nov-2000: DBFIND, DBFIND_ENTRY, DBFIND_SORT, DBSEARCH, IMDBASE - Now
                have a Count keyword; deprecate use of !ERR

11-Oct-2000: DBXVAL - Work for multiple-valued strings

08-Aug-2000: DBPRINT - Change a loop index to type LONG (sigh...)

5-Feb-2000:  DBPRINT - Only byteswap when necessary, for much improved speed.

1-Nov-1999:  DBINDEX, DBEXT_DBF - Now allow a maximum of 18 instead of 15 items



 
