NAME

pset - Set the value of one or more parameters for a specified tool or parameter file.

USAGE

pset [ -f ] tool-or-par-file-name [ parameter-args ]

DESCRIPTION

pset sets parameter values for the specified task or parameter file. The list of "parameter-args" may either be positional assignments - i.e. values simply listed in the order for which they would be prompted - or absolute (or keyword) assignments, i.e. specified in parameter=value pairs whose order is unimportant (see examples below).

If no parameter assignments are specified, pset will prompt for a new value for each parameter in the parameter file. Both hidden and non-hidden parameters are prompted for, with default values displayed in brackets. Users may input a new value or a carriage return to keep the default value.

Behavior of this task depends upon the value of the PFILES environment variable, which is used to specify the location of parameter files. The PFILES variable uses a semicolon delimiter to separate two types of parameter directories: 

     <user>;<system>
The first path ("user") is one or more "local" (writeable) parameter directories (typically $HOME/pfiles for a default HEASoft setup), and the second path ("system") is one or more read-only parameter directories (typically $HEADAS/syspfiles). When both paths are equivalent, one may omit the semicolon and duplicate path (for example, when developing a new task, one might set PFILES="." to use only the current working directory). Multiple colon-delimited directories are allowed in both portions of the PFILES variable: 

     <user1>:<user2>;<system1>:<system2>
The default values from the first "system" path are used the first time a task is run, or whenever the default values have been updated more recently than the user's copy of the parameters. The user's copy is created when a task terminates, and retains any learned changes to the parameters.

This task will look for a copy of the specified parameter file (or parameter file for the specified task) in the first "user" parameter directory; if the file does not exist there, it will then search all subsequent directories listed in PFILES.

The "-f" flag may be used to disable searching of directories listed in the PFILES variable, allowing instead for specification of a particular parameter file (with a preceding directory path if the file is not in the current working directory).

EXAMPLES

1. In ftverify.par, set the parameter 'infile' to "test.fits" and 'prstat' to the value "no" using positional assignments, in which the order of value assignments must match the order in which they are listed in the parameter file: 

    % pset ftverify.par test.fits no
2. In ftverify.par, set the parameter 'infile' to "test.fits" and 'prstat' to the value "no" using absolute assignment, in which the order of parameter=value pairs is unimportant: 

    % pset ftverify.par prstat=no infile=test.fits
3. Set the parameter 'prstat' in ftverify.par to the value "no", disabling the default search of directories listed in PFILES and instead providing the path to a specific parameter file: 

   % pset -f /local/data/test/ftverify.par prstat=no

SEE ALSO

pget, plist, pquery, pquery2, punlearn

LAST MODIFIED

Aug 2016