The most frequently used ASTERIX packages of subroutines are described in the documents PROG_003, 004, 005 and 006, which should be consulted before writing an ASTERIX application. Subroutines in ASTLIB are organised by name using a system of prefixes. A list of the currently allowed prefixes and their meanings can be viewed by typing PREFIX (after invoking ASTDEV). All these routines reside in ASTLIB, and are more fully documented in their program headers, which may be inspected with DOCLIB.
Several Starlink subroutine packages are also important: the main HDS access routines are (mostly) documented in SUN92, the PRIMDAT routines (useful for simple mathematical manipulation of mapped arrays) are described in SUN39 and the CHR_* character string manipulation package in SUN40. Brief descriptions of ADAM subroutines (such as PAR_* and DAT_ASSOC) may be found in SG4, and detailed documentation within directory ADAM_DOCS. Several other packages such as SLALIB (SUN67), may be useful for specific applications. These can mostly be spotted by inspecting the Starlink documentation list in DOCSDIR:DOCS.LIS.