New FITSIO/CFITSIO Releases

[William Pence]

                 New Releases of FITSIO and CFITSIO
                 ----------------------------------
                           2 April 1997

New versions of the FITSIO (Fortran) and CFITSIO (C) libraries for
reading and writing FITS format data files are now available.  The main
new features in these releases are:

CFITSIO (v1.21):

  Provides a more transparent interface for reading and writing unsigned
  integers in FITS images and binary tables.  The CFITSIO interface now
  effectively supports unsigned 16-bit and 32-bit integers as basic FITS
  data types, although in fact the unsigned integers are stored in FITS
  files as signed integers with an appropriate offset as specified by the
  BZERO or TZEROn keyword (which completely conforms to the current
  FITS Standard).  There is a new section in the CFITSIO User's Guide
  that describes how to use these new features to read or write unsigned 
  integers.

FITSIO (v5.00)

  The data I/O throughput of FITSIO is now about twice as fast as in
  previous releases making it similar in performance to that of CFITSIO.
  FITSIO and CFITSIO now have nearly identical throughput when reading or
  writing FITS images, and rates of 2 - 6 MB/s are typical on current
  workstations.  Read rates greater than 50 MB/s have been recorded when
  the FITS image is cached in RAM memory.  FITSIO remains a little slower
  than CFITSIO (by up to a factor of 2) when reading or writing FITS
  binary tables due in part to the efficient use of C pointers and
  structures in CFITSIO which is difficult to reproduce in FITSIO when
  using Fortran-77.

  FITSIO has also been modified to be Fortran-90 compatible.  A new
  version of the machine-specific set of subroutines written using 
  Fortran-90 is provided which should work with most F90 compilers.

FITSIO and the CFITSIO may both be obtained on the WWW from:
 
    http://heasarc.gsfc.nasa.gov/fitsio
 
or by anonymous ftp from:

    legacy.gsfc.nasa.gov in the software/fitsio directory.

_________________________________________________________________________ 
William Pence
HEASARC - High Energy Astrophysics Science Archive Research Center
NASA/GSFC
e-mail: pence at tetra.gsfc.nasa.gov
phone: (301)286-4599