This application lists the FITS header stored in an NDFFITS extension. The list may either be reported
directly to you, or written to a text file. The displayed list of headers
can be augmented, if required, by the inclusion of FITS headers
representing the current World Co-ordinate System defined by the
WCS component in the NDF (see Parameter ENCODING).
If a non-null value is supplied, the NDF WCS component is used
to generate a set of FITS headers describing the WCS, and these
headers are added into the displayed list of headers (any WCS
headers inherited from the FITS extension are first removed). The
value supplied for ENCODING controls the FITS keywords that will
be used to represent the WCS. The value supplied should be one of
the encodings listed in the ``World Co-ordinate Systems'' section
below. An error is reported if the WCS cannot be represented using
the supplied encoding. A trailing minus sign appended to the
end of the encoding indicates that only the WCS headers should be
displayed (that is, the contents of the FITS extension are not
displayed if the encoding ends with a minus sign). Also see the
FULLWCS parameter. [!]
FULLWCS = _LOGICAL (Read)
Only accessed if ENCODING is non-null. If TRUE then all
co-ordinate frames in the WCS component are written out.
Otherwise, only the current Frame is written out. [FALSE]
IN = NDF (Read)
The NDF whose FITS extension is to be listed.
LOGFILE = FILENAME (Read)
The name of the text file to store a list of the FITS
extension. If it is null (!) the list of the FITS extension
is reported directly to you. [!]
The contents of the FITS extension in NDF saturn are
reported to you.
fitslist saturn fullwcs encoding=fits-wcs
As above but it also lists the standard FITS world-co-ordinate
headers derived from saturn's WCS component, provided such
information exists.
fitslist saturn fullwcs encoding=fits-wcs-
As the previous example except that it only lists the standard
FITS world-co-ordinate headers derived from saturn's WCS
component. The headers in the FITS extension are not listed.
fitslist ngc205 logfile=ngcfits.lis
The contents of the FITS extension in NDF ngc205 are
written to the text file ngcfits.lis.
Notes:
If the NDF does not have a FITS extension the application will
exit.
World Co-ordinate Systems
The ENCODING parameter can take any of the following values.
"FITS-IRAF" -- This uses keywords CRVALi
CRPIXi, CDi_j, and is the system commonly
used by IRAF. It is described in the document ``World
Coordinate Systems Representations Within the FITS Format''
by R.J. Hanisch and D.G. Wells, 1988, available by ftp from
fits.cv.nrao.edu /fits/documents/wcs/wcs88.ps.Z.
It is very similar to "FITS-IRAF" but supports a wider range of
projections and co-ordinate systems.
"FITS-WCS(CD)" -- This is the same as "FITS-WCS" except
that the scaling and rotation of the data array is described by
CD matrix instead of a PC matrix with associated CDELT values.
"FITS-PC" -- This uses keywords CRVALi,
CDELTi, CRPIXi, PCiiijjj, etc,
as in a previous (now superseded) draft of the above
FITS world co-ordinate system paper by E.W. Greisen and
M. Calabretta.
"FITS-AIPS" -- This uses conventions described in the
document ``Non-linear Coordinate Systems in AIPS'' by Eric W.
Greisen (revised 9th September, 1994), available by ftp from
fits.cv.nrao.edu /fits/documents/wcs/aips27.ps.Z. It is
currently employed by the AIPS data analysis facility, so its
use will facilitate data exchange with AIPS. This encoding
uses CROTAi and CDELTi keywords to describe
axis rotation and scaling.
"FITS-AIPS++" -- This is an extension to "FITS-AIPS" that
allows the use of a wider range of celestial projections, and is
used by the AIPS++ project.
"FITS-CLASS" -- This uses the conventions of the CLASS
project. CLASS is a software package for reducing single-dish
radio and sub-mm spectroscopic data. It supports double-sideband
spectra.
"DSS" -- This is the system used by the Digital Sky Survey,
and uses keywords AMDXn, AMDYn, PLTRAH,
etc.
"Native" -- This is the native system used by the AST
library (see SUN/210), and provides a loss-free
method for transferring WCS information between AST-based
application. It allows more complicated WCS information to be
stored and retrieved than any of the other encodings.
