The output file is component lookup table. This table is used by the synphot software and associated a component mnemonic with the name of the throughput table containing the component throughput. In order to produce the component lookup table, the software must open each of the throughput tables mentioned in it. Therefore, this task must be run from a machine where the full set of synphot throughput tables is accessible.
An optional useafter date can also be supplied on the command line. If
the useafter date is supplied, the throughput tables included in the
component lookup table will all have useafter dates less than the date
you supply. If no useafter date is supplied, the useafter date will
default to the current date. The date parameter taskes the form
(date=month-dd-yyyy-hh:mm:ss), for example,
(date=mar-15-1994-23:12:05). Case is not significant in the month
name and it may be abbreviated to any unique abbreviation of the month
name. The time of day is on a 24 clock. It is optional and defaults to
midnight if not supplied. The seconds field is optional if the time of
day is supplied.
thrucat.dat. The throughput catalog
contains two columns. The first column contains filename wildcard
patterns used to match the root name of the throughout file. The second
column contains the directory that throughput files matching that
pattern can be found in. The directory name is given as an iraf
logical.
Mkcomptab uses the directory file, directory.dat, to translate
between iraf logical directory names and operating system directory
names. The directory file has two columns. The first column contains
the name of the iraf logical and the second name contains the
translation to the operating system directory name. Subdirectories
within the second column are separated by slashes regardless of the
host operating system. If the translation does not start with a
leading slash, the directory is treated as a subdirectory of the top
level CDBS directory. This allows the same directory file to be used on
different systems as long as the same subdirectory structure is used.
The directory containing the data files is specified by the C macro
DATADIR and the top level CDBS directory is specified by the macro
CDBS_DIR. Both are defined in the include file system.h.
The names of the throughput catalog and directory file
are compiled into the program and are not modifiable by the
user at run time. They are controlled by the C macros THRUCAT_NAME,
and DIRECTORY_NAME, respectively, and are defined in the include
file datafile.h.
mkcomptab is named task. It calls
mkcomptab to create a load file containing the component lookup
table and write_sdastab to write it out as an SDAS format table.
Mkcomptab calls init_comptab to create an empty component
lookup table, comptab_query to fill the table from the CDBS
database, and update_comp to modify the table using information
from the throughput files. Init_comptab writes the required header
keywords to the loadfile and then creates empty table
columns. Comptab_query retrieves the names of the latest version
of each component throughput file from the CDBS database. Along with
the filename it also retrieves the component mnemonic, the comment,
the installation date, and the useafter date. All this information,
except the useafter date, is written to a row in the loadfile. The
useafter dates are used to compute the useafter date of the component
lookup table, which is written to the table header. Update_comp
looks at each throughput file mentioned in the lookup table. First, it
gets the directory name by looking it up in thrucat.dat. Then
update_comp calls getthrucol to get the name of the table
column containing the throughput information. If the name of the
column storing the throughput information is some other name than
THROUGHPUT, it place the column name in brackets after the
filename in the lookup table. If it is a parameterized throughput
table, the value of the parameter is removed from the column name
first.
Getthrucol in turn calls getthrulist to get a list of all the
throughput columns in the table. If there is more than one, it calls
similar to choose which throughput column name most closely
matches the component mnemonic. Getthtrulist calls xlate_fname
to translate the throughput file name from an iraf logical name to a
host operating system name. It then opens the table and adds all
columns except the wavelength and error columns to the list. If a
throughput column is parameterized, it removes the parameter value
before adding it to the list. Xlate_fname reads the dictionary
file and substitutes for any string in the filename ending with a
dollar sign. The substitution is done repeatedly, so iraf logicals in
the directory file can be defined in terms of other iraf logicals. If
the resulting directory name does not begin with a slash, the
directory name is appended to the directory defined by the macro
CDBSDIR.
CDBS_SERVER_2 sets the database server the task
accesses. CDBS_DB sets the name of the cdbs database that is used
by the task. DADS_DB sets the name of the dads database that is
used by the task. And CDBS_USER sets the user name used to access
the database. If these environment variables are not set, they default
to ZEPPO, cdbs_ops, dads_ops, and a public cdbs account.
In addition to these environment variables that control cdbs access,
the stdb library that this task is linked with requires the two
environment variables SYBASE and ACAREA be set. These
variables define the location of the Sybase and stdb executables and
libraries.