CFITSIO v2.0 Release

William Pence pence at tetra.gsfc.nasa.gov
Tue Nov 10 15:05:02 EST 1998


.                     **** CFITSIO v2.0 Release ****

The full (not beta) v2.0 version of the CFITSIO library for reading and
writing  FITS files has been officially released and is available at

     http://heasarc.gsfc.nasa.gov/fitsio

This release is backward compatible with the previous v1.42 release, and
contains many major new features, including:

1.  CFITSIO can now read IRAF format image files (.imh files) as well as
    FITS files. Thus, any program that uses CFITSIO to do image analysis
    of FITS images will be able to directly read IRAF images as well.

2.  Any FITS file on the internet can be directly accessed by providing the
    full FTP or HTTP URL to CFITSIO's open_file routine.

3.  Input FITS files can be filtered or modified at run-time based on a
    user-supplied expression that is appended to the name of the input file. 
    This allows users, at run time, to:

  a) select a subset of the rows in a table which satisfy an 
     arbitrarily complex boolean expression

  b) create new table columns whose values are calculated 
     as a function of other columns and/or keywords in the table

  c) create a virtual FITS image by binning/histogramming
     the values in one or more table columns.  This is most often 
     used to create an image by binning a list of X and Y coordinates
     for each event in a table.

   These file filtering routines use new extremely fast, state-of-the-art
   algorithms. Effective file I/O throughput rates of 5 - 10 MB/s are
   typical on current generation workstations or PCs.

4.  A Fortran-callable interface is provided, so CFITSIO routines may be
    easily called from Fortran programs as well as from C.

5.  The Users Guide has been greatly improved.


Acknowledgements: Many people and institutions have contributed to the 
new features in CFITSIO, including:

Jurek Brokowski, Bruce O'Neel, and Don Jennings at the Integral Science Data
Center (ISDC), in Switzerland designed the concept of plug-in I/O drivers
for CFITSIO 2.0. This greatly simplified the low-level I/O which in turn
made other new features such as support for compressed FITS files and IRAF
image files much easier to implement. They provided the ftp, http, root, and
shared memory file drivers.  They are also responsible for providing the
template file parsing routines and the hierarchical grouping routines.

Uwe Lamers, at XMM/ESA/ESTEC, provided the fast lexical parsing algorithm
that is used by CFITSIO to filter table rows at run time. This algorithm in
effect compiles the expression, so that it does not need to be reinterpreted
for every row of the table. Peter Wilson (RSTX, NASA/GSFC) recoded this 
parsing algorithm  in C and combined it with the CFITSIO iterator
function for even faster throughput. He also added support for all the
FITS datatypes and null values. 

The file filtering and binning syntax used by CFITSIO is modelled on a
similar syntax developed by Jonathan McDowell and collaborators at the AXAF
Science Center. 

Doug Mink (SAO) provided the routines for converting IRAF format images into
FITS format. 
____________________________________________________________________
Dr. William Pence                          pence at tetra.gsfc.nasa.gov
NASA/GSFC Code 662         HEASARC         +1-301-286-4599 (voice)     
Greenbelt MD 20771                         +1-301-286-1684 (fax)



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