TABLES provides support for tabular data for STSDAS and other packages. Many types of data are stored in tabular format, such as catalogs of astronomical objects, spectral data (e.g. columns of wavelength and flux), and coefficients of fit to data. TABLES provides a programming interface for accessing tables, and it includes a collection of utility programs for working with tables. FITS tables, STSDAS format, and simple text tables are supported. The programming interface is used for the utility programs in TABLES, by tasks in STSDAS, and by other external packages. The utility programs are used for such tasks as plotting, selecting rows based on an expression involving column values, sorting rows in a table, joining tables, and performing arithmetic operations on column values.
TABLES is an 'external package' in IRAF. That is, TABLES is not a part of the IRAF core system, but it can be obtained separately and used within the IRAF CL (or in PyRAF). From within the IRAF CL or PyRAF, TABLES can be loaded (the tasks can be made available) by typing `tables'.
The programs (IRAF tasks) in this package make use of a library of table I/O functions, which is included in TABLES. Users can write their own tasks that make use of these functions, and then link with this library. Fortran and SPP interfaces are provided in TABLES, and a C interface is included with the STSDAS package.
The TABLES package sits alongside STSDAS and provides tools and libraries for working with tabular data. STSDAS requires TABLES, but one may use TABLES without STSDAS. Together, these two packages comprise STSDAS/TABLES.
Both STSDAS and TABLES are products of the Science Software Branch at STScI.