ISOCAM Interactive Analysis User's Manual Version 5.0 - ISO - ESA

Chapter 18
Export of CIA data structures
Many CIA users probably also use non-IDL based analysis packages, such as IRAF 1 .Themost
convenient way to share data with such external packages is by using the FITS format. Due to
the inability of many external packages to handle extended FITS files we need to use both nonextended
and extended FITS. It is impossible to export all data from a CIA structure without
using FITS extensions, so for archiving purposes FITS extensions are unavoidable. With these
problems in mind two kinds of export have been developed: (i) export for external analysis using
non-extended FITS and (ii) export for archiving using FITS extensions. A small exception to
this rule has been made with the routine conv cvf2isap.
18.1 Export to the spectral analysis package ISAP
conv cvf2isap allows export of ISOCAM CVF data to the spectral analysis package ISAP:
CIA> conv_cvf2isap, cvf_pds, ’cvf_isap.fits’
As you may guess bf conv cvf2isap accepts a CVF PDS as input. As output it writes a
FITS file with extensions that can be understood by ISAP. The keyword option /pix accepts
a two element integer array specifying an ISOCAM pixel and a spectrum is extracted a this
pixel position. bf conv cvf2isap also works with ISOCAM CVF AAR products – in this case it
accepts the name of a CMAP file as input.
18.2 Export to external packages
This section describes CIA routines for export of data, to non-extended FITS files, for analysis
by external packages.
raster2fits writes the raster PDS fields .RASTER, .RMSRASTER and .NPIXRASTER to a
FITS primary array.
CIA> raster2fits, raster_pds, name=’raster.fits’
The keyword option /iraf will make the FITS file compatible with the IRAF preferred CD
matrix format of CDx y, instead of CD00x00y, and only .RASTER will be written to the
1 It appears that MIDAS has a problem reading CIA generated FITS files – see Section 2.4.
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