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Getting Help

General help information about FTOOLS as well as detailed help on each individual task can be obtained by the fhelp task. Type,

> fhelp ftools

to get a brief description of the FTOOLS package. To get detailed help on any particular FTOOLS task type,

> fhelp <taskname>

where <taskname> is the name of the task you are interested in. The help files give a description of what each task does and a description of all the required and optional (hidden) parameters. It is important to realize that when running an FTOOLS task you will only be required to enter values for the most important parameters, such as the name of the input FITS file. But most of the tasks also have other `hidden' parameters which have a predefined value unless you explicitly reset them to a new value. These hidden parameters can significantly alter the operation of the task, so you need to be aware of what hidden parameters are available for a given task and what their default values are. One way to determine this is to read the help file for the task with the fhelp command, but a quicker way to simply see all the task parameters and their current values is with the plist command (analogous to the lpar command in IRAF). For example:

> plist fkeyprint

        infile =                  Name of FITS file and [ext#]
       keynam =                  Enter the keyname (8 characters or less)
     (outfile = STDOUT)          Name of optional output file
       (exact = no)              Exact string or not
     (clobber = no)              Overwrite existing output file?
        (mode = ql)

shows that the fkeyprint task has 4 hidden parameters (by convention, the names of hidden parameters are enclosed in parentheses) to control the name of an optional output file where the keyword value should be written, whether to do string matching exactly or to match only as many characters as given, whether to overwrite an existing output file, and the mode parameter which determines how non-hidden parameters should be handled. By changing mode to 'h' you can ``hide'' all of your parameters, for instance. This can be dangerous and is not recommended for casual users.

A prompt for a parameter will generally display the default value for that parameter based on what was entered the last time the tool was run or was set using pset. Hitting ``return'' will select this value. Some FTOOLS tasks (particularly within the Xronos sub-package) will also calculate a default value for some of their parameters based on other input parameters. This default can be selected by typing ``INDEF''

next up previous
Next: Running a task Up: A Brief FTOOLS Tutorial Previous: A Brief FTOOLS Tutorial

Lawrence Elwin Brown
Wed Aug 6 11:33:26 EDT 1997


If FTOOLS has been useful in your research, please reference this site ( and use the ASCL reference for HEASoft [ascl:1408.004] or the ASCL reference for the original FTOOLs paper [ascl:9912.002]:

Blackburn, J. K. 1995, in ASP Conf. Ser., Vol. 77, Astronomical Data Analysis Software and Systems IV, ed. R. A. Shaw, H. E. Payne, and J. J. E. Hayes (San Francisco: ASP), 367.

Web page maintained by: Bryan K. Irby