Introduction to TABLES
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.
The current release of STSDAS/TABLES is v3.7 (15 June 2007).
Last updated: 18 June 2007
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