application extracts the values of FITS
keywords from a FITS extension
in an NDF
uses them to construct another NDF extension. The list of new extension components
required, their data types and the names of the FITS keywords from which to derive
their values are specified in a keyword translation table
held in a separate text
fitsimp ndf table xname xtype
NDF = NDF (Read and
The NDF in which the new extension is to be created.
TABLE = FILENAME
The text file containing the keyword translation table. The format of this
file is described under “Table Format”
XNAME = LITERAL (Read)
The name of the NDF
extension which is to receive the values read from the FITS extension . If this
extension does not already exist, then it will be created. Otherwise, it should be a
scalar structure extension within which new components may be created (existing
components of the same name will be over-written). Extension names may contain up to 15
alpha-numeric characters, beginning with an alphabetic character.
XTYPE = LITERAL
The HDS data type
of the output extension. This value will only be
required if the extension does not initially exist and must be created. New
extensions will be created as scalar structures.
fitstable ccdinfo ccd_ext Creates a new extension called CCDINFO (with a
data type of CCD_EXT) in the NDF structure called datafile. Keyword values
are read from the NDF’s FITS extension and written into the new extension as
separate components under control of a keyword translation table held in the
fitsimp ndf=n1429 table=std_table xname=std_extn FITS
keyword values are read from the FITS extension in the NDF structure n1429 and
written into the pre-existing extension STD_EXTN under control of the translation
std_table. Components which already exist within the extension may be
over-written by this process.
Approximately proportional to the number
of FITS keywords to be translated.
The keyword translation
table should be held in a text file, with one extension component specified per
line. Each line should contain 3 fields, separated by spaces and/or tabs, as
Field 1: The name of the component in the output extension for which a value is to be
Field 2: The data type of the output component, to which the keyword value will be
converted (one of
Field 3: The name of the FITS keyword from which the value is to be obtained.
Hierarchical keywords are permissible; the format is concatenated keywords joined with
full stops and no spaces, e.g.
Comments may appear at any point in the table and should begin with an exclamation
mark. The remainder of the line will then be ignored.