WCSSHOW

Examines the internal structure of a WCS description.

Description:

This application allows you to examine WCS  information (represented by an AST Object) stored in a specified NDF  or HDS  object, or a catalogue. The structure can be dumped to a text file, or a Graphical User Interface can be used to navigate through the structure (see Parameter LOGFILE). A new FrameSet can also be stored in the WCS component  of an NDF (see Parameter NEWWCS). This allows an NDF WCS component to be dumped to a text file, edited, and then restored to the NDF.

The GUI main window contains the attribute values of the supplied AST Object. Only those associated with the Object’s class are displayed initially, but attributes of the Objects parent classes can be displayed by clicking one of the class button to the top left of the window.

If the Object contains attributes  which are themselves AST Objects (such as the Frames within a FrameSet), then new windows can be created to examine these attributes by clicking over the attribute name.

Usage:

wcsshow ndf object logfile newwcs full quiet

Parameters:

CAT = FILENAME (Read)
A catalogue containing a positions list such as produced by applications LISTMAKE, CURSOR. If supplied, the WCS Information in the catalogue is displayed. If a null (!) is supplied, the WCS information in the NDF specified by Parameter NDF is displayed. [!]
FULL = _INTEGER (Read)
This parameter is a three-state flag and takes values of -1, 0, or +1. It controls the amount of information included in the output generated by this application. If FULL is zero, then a modest amount of non-essential but useful information will be included in the output. If FULL is negative, all non-essential information will be suppressed to minimise the amount of output, while if it is positive, the output will include the maximum amount of detailed information about the Object being examined. [current value]
LOGFILE = FILENAME (Write)
The name of the text file in which to store a dump of the specified AST Object. If a null (!) value is supplied, no log file is created. If a log file is given, the Tk browser window is not produced. [!]
NDF = NDF (Read or Update)
If an NDF is supplied, then its WCS FrameSet is displayed. If a null (!) value is supplied, then the Parameter OBJECT is used to specify the AST Object to display. Update access is required to the NDF if a value is given for Parameter NEWWCS. Otherwise, only read access is required. Only accessed if a null (!) value is supplied for CAT.
NEWWCS = GROUP (Read)
A group expression giving a dump of an AST FrameSet which is to be stored as the WCS component in the NDF given by Parameter NDF. The existing WCS component is unchanged if a null value is supplied. The value supplied for this parameter is ignored if a null value is supplied for Parameter NDF. The Base Frame in the FrameSet is assumed to be the GRID Frame. If a value is given for this parameter, then the log file or Tk browser will display the new FrameSet (after being stored in the NDF and retrieved). [!]
OBJECT = LITERAL (Read)
The HDS object containing the AST Object to display. Only accessed if Parameters NDF and CAT are null. It must have an HDS type of WCS, must be scalar, and must contain a single one-dimensional array component with name DATA and type _CHAR.
QUIET = _LOGICAL (Read)
If TRUE, then the structure of the AST Object is not displayed (using the Tk GUI). Other functions are unaffected. If a null (!) value is supplied, the value used is TRUE if a non-null value is supplied for Parameter LOGFILE or Parameter NEWWCS, and FALSE otherwise. [!]

Examples:

wcsshow m51
Displays the WCS component of the NDF m51 in a Tk GUI.
wcsshow m51 logfile=m51.ast
Dumps the WCS component of the NDF m51 to text file m51.ast.
wcsshow m51 newwcs=^m51.ast
Reads a FrameSet from the text file m51.ast and stores it in the WCS component of the NDF m51. For instance, the text file m51.ast could be an edited version of the text file created in the previous example.
wcsshow object=" /agi_starprog.agi_3800_1.picture(4).more.ast_plot"
Displays the AST Plot stored in the AGI database  with X windows picture number 4.