The Schedule File

The schedule file is the main, and perhaps only, input file that the user prepares. It provides bookkeeping information for telescope and correlator operators, points to the desired catalogs or contains segments of catalogs, gives overall control commands to describe the observations and lays out the detailed sequence of observing scans.

A large number of input parameters are available for the schedule file. They are all described in detail in this section. However, most of the parameters default to reasonable values for ordinary VLBI observations and can be ignored by most users. The easiest way to determine which ones to worry about is to follow one of the examples and consult the detailed descriptions only when unsure of the meaning or behavior of a parameter.

The descriptions of the parameters for the schedule file, and later for the setup files, contain a wealth of information about VLBI systems and scheduling style. Serious users might find it instructive to browse through these sections.

This section starts with list of the parameters, with one line per parameter and, for web users, a link. When a parameter is given as mixed upper and lower case, the lower case letters are optional in the input file. The main part of this section is the detailed descriptions of every parameter. These descriptions start with some text describing the parameter, its actions, and information about how to use it. Every parameter description ends with a short table giving the following information:

• Argument: The data type expected.
• Options: A list of specific options if appropriate.
• Default: The value assigned by SCHED if the parameter is not given in the schedule file.
• Usage: Can the parameter be specified for each scan or only once? If for each scan, what happens if it is specified for one scan and not the next.
• Example: An example specification of the parameter.

If a parameter for which SCHED only wants one value is specified for more than one scan, only the last value will be used. For parameters that can be specified for each scan, nearly all default to the value for the previous scan if not specified. The only exceptions are START, STOP, REP, GROUP, POINT, and COMMENT. Normal defaulting for these parameters would produce undesirable behavior. Note that TAPE, REWIND, FASTFOR, REVERSE, are not obsolete because they were specific to tape, which is no longer in use.